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Air Care Certified Emissions Repair Manual January 2010 © 2007 - 2010 Pacific Vehicle Testing Technologies Limited - All Rights Reserved

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Page 1: AirCare Repair Manual

AirCareCertified Emissions Repair Manual

January 2010

© 2007 - 2010 Pacific Vehicle Testing Technologies Limited - All Rights Reserved

Page 2: AirCare Repair Manual

Disclaimer of Liability

Neither the author, Pacific Vehicle Testing Technologies, TransLink, nor theProvince of British Columbia warrants or assumes any legal liability orresponsibility for the accuracy, completeness, or usefulness of anyinformation, apparatus, product, or process disclosed in this document.

Page 3: AirCare Repair Manual

Table of Contents

Chapter 1: Introduction

Air Pollution In The Lower Fraser Valley . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

AirCare Program Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5AirCare Program Goals and Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Vehicles Subject to AirCare . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Program Enforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Inspection Centre Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Inspection Centre Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Inspection Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Inspection Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Visual and Functional Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

OBD-II Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Exhaust Emission Inspections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Re-inspections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

About Pacific Vehicle Testing Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Who Is PVTT? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9PVTT's Vision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9PVTT's AirCare Mission Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

About This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Purpose Of This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10How To Use This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Symbols Used in This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Chapter 2: AirCare Certification

Certification Concept . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Requirements for AirCare Certification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Repair Centre Certification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Requirements For Repair Centre Certification. . . . . . . . . . . . . . . . . . . 16

Requirements For Repair Centre Re-certification . . . . . . . . . . . . . . . . 17

Repair Centre Performance Monitoring . . . . . . . . . . . . . . . . . . . . . . . 18

Performance Indicator Initiated Suspension Policy . . . . . . . . . . . . . . . . . . . . 18First Visit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Second Visit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Third Visit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

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Technician Certification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Requirements For Technician Certification . . . . . . . . . . . . . . . . . . . . . 20

Requirements For Re-instatement & New Technicians . . . . . . . . . . . . . 20

Fuel Type Endorsement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Technician Identification Cards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Technician Responsibilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21What Is Expected Of The Technician . . . . . . . . . . . . . . . . . . . . . . . . . 21

What Is Beyond The Control Of The Technician . . . . . . . . . . . . . . . . . 22

The Repair Effectiveness Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22The Logic Of The REI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

REI for Tailpipe Inspections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

REI for OBD Inspections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Second Chance REI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Individual REI vs. Average REI. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

REI Implications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Performance Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

What Causes Mid-Range Average REIs . . . . . . . . . . . . . . . . . . . . . . . 26

How Mid-Range Average REIs Can Be Prevented . . . . . . . . . . . . . . . . 26

What Causes Sub-Par REIs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

How Sub-Par REIs Can Be Prevented . . . . . . . . . . . . . . . . . . . . . . . . 27

Technician Performance Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . 28

Chapter 3: Vehicle Inspection Report

Purpose of the VIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Emissions Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Tailpipe Testing Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32On-Board Diagnostic Testing Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Detailed Explanation Of The VIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Inspection Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Vehicle Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34On Board Diagnostic Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Driving Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Idle Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

What You Can Learn From The VIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Chapter 4: Detailed Inspection Data

Types of Detailed Inspection Data Available . . . . . . . . . . . . . . . . . . . . . . . . . 41Detailed Emissions Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Detailed Data For Other Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Page 5: AirCare Repair Manual

OBD Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Aborted Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Sources of Detailed Inspection Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Chapter 5: Diagnostic Trace Report

Purpose of the DTR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Detailed Explanation Of The DTR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Using The DTR To Assist Your Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

IM240 DTRs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

IM240 DTR Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

ASM DTRs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

ASM DTR Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

D147 DTRs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

D147 DTR Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Chapter 6: Obtaining Additional Diagnostic Information

Detailed Inspection Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59How To Obtain Detailed Data Reports . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59How To Read the Second By Second (SBS) Reports . . . . . . . . . . . . . . . . . . . 60How The SBS Readings Can Assist Your Diagnosis . . . . . . . . . . . . . . . . . . . . 62

Previous Inspections and Repairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63How To Obtain Previous Inspection and Repair Information . . . . . . . . . . . . . 63How Historical Information Can Assist Your Diagnosis . . . . . . . . . . . . . . . . . 63

Previous Inspection Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Previous Repair Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Chapter 7: OBD Diagnostic Procedures

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67OBD II Operational Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Readiness Monitors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

AirCare Readiness Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Understanding OBD Failures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71The Diagnostic Process - OBD Failures . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Gather Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Review OBD Inspection Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Check For Any Related Service Bulletins . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Record DTCs and Freeze Frame Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

DTCs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Freeze Frame Records. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Remember the Possibility of Hidden or Blocked DTCs . . . . . . . . . . . . . 74

Page 6: AirCare Repair Manual

Pinpointing the Defect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76General Guidelines For Diagnosing and Repairing OBD Failures . . . . . . . . . . . 76Establishing Priorities on Failures With Multiple DTCs . . . . . . . . . . . . . . . . . . 76OBD Communication Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Preparing the Vehicle For Re-inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Verify Your Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Setting Readiness Monitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78If You Have Trouble Getting All Monitors To Run . . . . . . . . . . . . . . . . . . . . . 79

Special Note Regarding 1998 Volvo OBD Monitors . . . . . . . . . . . . . . . 79

Other Alternatives You May Want To Consider . . . . . . . . . . . . . . . . . . . . . . 80

Don’t Clear the DTCs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

Have the Customer Complete the Readiness Monitors. . . . . . . . . . . . . 80

Chapter 8: Diagnostic Procedures

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85The Diagnostic Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86Baselining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86Understanding Exhaust Emissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

Gas Analysis In a Nutshell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Emissions vs. Air Fuel Ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

Review Inspection Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90IM240 Results Interpretation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90ASM Results Interpretation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91Idle Test Interpretation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92D147 Results Interpretation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

Prioritizing Component Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94Establishing Priorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94Are Other Problems Being Masked? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96Possible Causes of High HC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

Other Sources of HC Besides the Tailpipe . . . . . . . . . . . . . . . . . . . . . 97

HC Problems and Alternative Fuels . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Possible Causes of High CO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98Possible Causes of High NOx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99Possible Causes of High Diesel Opacity . . . . . . . . . . . . . . . . . . . . . . . . . . . .100

Performing Component Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103O2 Sensor Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103

Snap-Throttle Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

More Conclusive O2 Sensor Response Time Test . . . . . . . . . . . . . . . 106

Cross Counts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

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Zirconia vs. Titania O2 Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

Catalytic Converter Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108Before and After Sampling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

Guidelines For Acceptable Catalyst Efficiency . . . . . . . . . . . . . . . . . . 110

Tips for Upstream Sampling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

Other Methods of Catalyst Testing . . . . . . . . . . . . . . . . . . . . . . . . . 110

Induction System Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114Induction System Basic Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

Air/Vacuum Leak Testing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

Ignition System Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115Ignition System Basic Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

Ignition Analyser/Oscilloscope Testing . . . . . . . . . . . . . . . . . . . . . . 115

Crankcase Vapor Control System Testing . . . . . . . . . . . . . . . . . . . . . . . . . .116Positive Crankcase Ventilation (PCV) Valve or Orifice . . . . . . . . . . . . 116

Crankcase Pressure and Oil Contamination . . . . . . . . . . . . . . . . . . . 116

Evaporative Control System Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Visual Inspection of EVAP System Components . . . . . . . . . . . . . . . . 117

Functional Testing of EVAP System Components . . . . . . . . . . . . . . . 117

Fuel System Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .117Carburettor (non-feedback) Tests. . . . . . . . . . . . . . . . . . . . . . . . . . 117

Feedback Carburettor Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

Fuel Injection System Tests. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

Other Fuel System Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126

Propane or Natural Gas Fuel System Tests . . . . . . . . . . . . . . . . . . . 127

Air Injection System Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128EGR System Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .128

EGR System Basic Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

EGR Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

EGR Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

Engine Integrity Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130Power Balance Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

Compression Test and Cylinder Leakdown Test . . . . . . . . . . . . . . . . 130

Combustion Chamber Deposits . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

Chapter 9: Obtaining Technical Assistance

Contacts At PVTT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135AirCare TechLine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135RepairNet Help . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135Technician and Repair Centre Certification . . . . . . . . . . . . . . . . . . . . . . . . .135AirCare Program & Certification Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . .135Program Auditor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135Other Sources of Information and Assistance . . . . . . . . . . . . . . . . . . . . . . .135

Page 8: AirCare Repair Manual

Chapter 10: Repair Cost Estimates

The Importance Of Your Repair Cost Estimate . . . . . . . . . . . . . . . . . . . . . . . .139

What To Include In Your Repair Cost Estimate . . . . . . . . . . . . . . . . . . . . . . . .139

Revising Your Estimate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139

Chapter 11: Repair Cost Limits

Understanding Repair Cost Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143Why Repair Cost Limits Exist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143How The Repair Cost Limits Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143

Using Repair Cost Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .144Examples Of How The Repair Cost Limits Apply . . . . . . . . . . . . . . . . . . . . . .144

Entire Repair Within Cost Limit. . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Partial Repair Within Cost Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

No Repair Within Cost Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Current Repair Cost Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145

Chapter 12: Complete Repairs vs. Partial Repairs

The Problems With Incomplete Repairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . .149

Obtaining Repair Authorization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150Helping Your Customer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150Helping Yourself . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150

Chapter 13: The Repair Data Form (RDF)

The Importance Of The Repair Data Form . . . . . . . . . . . . . . . . . . . . . . . . . . .153

How To Complete The RDF on RepairNet . . . . . . . . . . . . . . . . . . . . . . . . . . . .154

More Details on Each Section Of The RDF . . . . . . . . . . . . . . . . . . . . . . . . . . . .156Vehicle Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .156

Estimated Cost. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

Actual Parts Cost . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

Actual Labour Cost . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

Work Order No. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

Warranty. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

O2 / AF Sensor(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .157Maximum Voltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

Minimum Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

Cross Counts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158

Response Time. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158

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Repair Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .158Air Induction System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158

Catalytic Converters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158

Computer Controls General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

Computer Controls - Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

Computer Controls - Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

EGR System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160

Emissions Controls - Other . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160

Engine Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160

Evaporative Control System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160

Fuel Delivery System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160

Ignition System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161

Additional Diagnostic / Repair Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161The Repair Data Confirmation Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161Hardcopy Repair Data Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .162

Chapter 14: Re-inspections

Re-inspection Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165

Conditional Passes (Waivers) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165Cost Waiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165Qualified Waiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165

Chapter 15: Customer Complaints

Reasons For Customer Complaints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169

PVTT's Role In Emissions Repair Complaints . . . . . . . . . . . . . . . . . . . . . . . . .169

Resolving Customer Complaints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Is The Complaint Justified? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Unexpected Re-inspection Result? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170Unrealistic Expectations? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170

Unresolved Customer Complaints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .171

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Appendix A: Engine Exchanges

Engine Change Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A-3

Appendix B: Specialty Vehicle Information

About Specialty Vehicles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-3

Inspection Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-5

Common Issues For Specialty Vehicles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .B-7

Appendix C: Alternative Fueled Vehicle Information

OEM Alternative Fuel Vehicles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-3

Conversion to Alternative Fuels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-4

Appendix D: Permissible Use Of AirCare® Mark

The AirCare Logo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-3

Appendix E: AirCare Certified Repair Centre Requirements

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List of Figures

Figure 1 - Code of Practice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17

Figure 2 - Vehicle Inspection Report (VIR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

Figure 3 - Diagnostic Trace Report (DTR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45

Figure 4 - Driving Trace For Each Type of Dynamometer Test . . . . . . . . . . . . . . . . . . . . . . . . .46

Figure 5 - IM240 DTR - 1992 4.0L Light-Duty Truck Running Normally . . . . . . . . . . . . . . . . . .49

Figure 6 - IM240 DTR - NOx Failure Due To Dirty MAF Sensor . . . . . . . . . . . . . . . . . . . . . . . .50

Figure 7 - IM240 DTR - CO and HC Failure Due To Leaking Injector . . . . . . . . . . . . . . . . . . . .51

Figure 8 - ASM DTR Graphs Showing What Appears To Be A Lazy Catalyst . . . . . . . . . . . . . . . .53

Figure 9 - ASM DTR For 1988 Vehicle Running Normally (Fast-Pass) . . . . . . . . . . . . . . . . . . . .54

Figure 10 - D147 DTR For 1995 Vehicle Running Normally . . . . . . . . . . . . . . . . . . . . . . . . . . .55

Figure 11 - D147 DTR Showing Extremely High Opacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56

Figure 12 - D147 DTR Showing After Repair Opacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56

Figure 13 - D147 DTR Showing After Repair Opacity - Same Scale As Fail DTR . . . . . . . . . . . . .56

Figure 14 - Detailed Data Links in Inspection History Section of RepairNet . . . . . . . . . . . . . . . .60

Figure 15 - Second By Second Graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61

Figure 16 - Second By Second Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61

Figure 17 - Exhaust Gas Analysis Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88

Figure 18 - Air Fuel Ratio Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89

Figure 19 - Emission Diagnosis Priorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95

Figure 20 - DSO Setup For Measuring O2 Sensor Range and Response . . . . . . . . . . . . . . . . . 105

Figure 21 - Reading Response Time On DSO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

Figure 22 - O2 Sensor Cross Counts on DSO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

Figure 23 - Catalytic Conversion Efficiency Formulae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

Figure 24 - Determining Catalyst Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

Figure 25 - O2 Sensor Waveforms at High Idle Indicating Good Catalyst . . . . . . . . . . . . . . . . 112

Figure 26 - O2 Sensor Waveforms Indicating Inefficient Catalyst . . . . . . . . . . . . . . . . . . . . . 113

Figure 27 - MAF Voltage Output Waveform (Snap Throttle) . . . . . . . . . . . . . . . . . . . . . . . . . 122

Figure 28 - MAF Sensor Linearity Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

Figure 29 - TPS Voltage Output Waveform (Snap Throttle) . . . . . . . . . . . . . . . . . . . . . . . . . . 125

Figure 30 - AirCare Logo Usage For Color Print . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-3

Figure 31 - AirCare Logo Usage For Black and White Print . . . . . . . . . . . . . . . . . . . . . . . . . . D-4

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Chapter 1Introduction

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Chapter 1 - Introduction

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Air Pollution In The Lower Fraser ValleyIf you have never personally experienced the effects of airpollution, consider yourself fortunate. Persons with asthma andother respiratory illnesses regularly experience extreme difficultyin breathing due to the air pollution in the Lower Mainland.

Although British Columbia has cleaner air than many other areas inNorth America, pollution levels are periodically higher thanCanada's National Ambient Air Quality Objectives (NAAQO) in theLower Fraser Valley. Ozone (O3) and carbon monoxide (CO) aretwo of the pollutants that reach unhealthy concentrations in theatmosphere.

Ozone is created when volatile organic compounds (VOCs) andoxides of nitrogen (NOx) emissions react together in the presenceof sunlight. To a lesser extent, carbon monoxide emissions alsocontribute to ozone formation by reacting with NOx.

HOW IS OZONE HARMFUL? In the upper atmosphere (the stratosphere), naturally occurringozone protects the surface of the earth from harmful ultravioletradiation, but at ground level, ozone can cause serious damage tohuman health and vegetation. High ozone levels cause shortnessof breath and eye irritation. Prolonged exposure has been linkedto reduced lung function.

Hydrocarbon (HC) emissions are classified as volatile organiccompounds (VOCs) and are also a product of incompletecombustion of fuels. Gasoline, diesel fuel, natural gas, andpropane are all hydrocarbon fuels. HC emissions are also causedby the evaporation of liquid hydrocarbons.

Oxides of nitrogen emissions occur when fuels are burned at hightemperature. Some of the nitrogen (N2) in the air combines withsome of the oxygen (O2) in the air to form nitric oxide (NO). In anengine, some of the NO undergoes additional reactions and turnsinto nitrogen dioxide (NO2). The emissions of NO and NO2 arecollectively referred to as NOx. In addition to contributing to theformation of ozone, NOx emissions also lead to a build up ofnitrogen dioxide levels in the atmosphere, which are known toincrease the risk of respiratory disease in children.

HOW IS CO HARMFUL? CO is an odorless and colourless gas, and high CO levels interferewith the ability of the bloodstream to carry oxygen. This causesthe heart to beat faster in order to meet the body's oxygendemand, a particular concern for people with heart ailments. HighCO levels are also associated with errors in judgement andimpaired fetal development (which is why pregnant women areencouraged to avoid smoking).

Carbon monoxide build-up in the atmosphere is caused byemissions from incomplete combustion. All naturally occurringfuels (such as coal, oil, natural gas, and wood) contain carbon.

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Products made from these natural resources (such as gasoline,methanol, diesel fuel, and liquefied petroleum gas) also containcarbon. When combustion is complete, the carbon in the fuel isconverted into carbon dioxide (CO2). When combustion isincomplete, some of the carbon is only partially burned and COemissions occur.

WHY AIRCARE? Motor vehicles are the primary cause of CO and NOx emissions inthe region and are also significant contributors of VOCs. In 2005,regional air quality estimates for the Lower Fraser Valleyconcluded that light-duty vehicles are still the largest source of

smog-forming pollutants1.

One of the reasons that light-duty vehicles produce such a largeportion of the emissions in the region is that many vehicles on theroad are not properly maintained. Vehicles with emissions defectscan emit over ten times the HC and CO emissions of a properlyrunning vehicle. Tampering with emission control systems can alsocause emissions to increase by a factor of ten.

The other key reason that light-duty vehicles produce such a largeportion of the emissions in the region is that there are so many ofthem. In areas having a large population of motor vehicles, aprogram designed to identify vehicles with emissions-relateddefects and have them repaired can substantially reduceemissions. Such programs are commonly referred to as emissionsinspection and maintenance (I/M) programs.

DOES AIRCARE WORK? Yes! Since 1992, total light-duty vehicle emissions have beenreduced by over 70 percent, despite significant growth in thenumber of vehicles operating in our region. Approximately 30%of this improvement is directly attributed to AirCare repairs,while the other portion is a result of the introduction of newvehicle technology and cleaner fuels.

An analysis performed by Levelton Consultants Ltd. and de la TorreKlausmeier Consulting, Inc. concluded that emission reductionsdue to AirCare are equivalent to removing 240,000 gasoline

passenger cars from the road.2

These are important points to remember. The bottom line is, aslong as vehicles break, and as long as motorists are able tocontinue to operate vehicles that are broke, the AirCare programcan make a positive difference in our community - but only if thosevehicles are repaired properly.

1. 2005 Lower Fraser Valley Air Emissions Inventory & Forecast and Backcast - Metro Vancouver - December 2007

2. AirCare Program Technical Review - Phase 1 - Levelton / de la Torre Klausmeier November 2004 (available for download at www.aircare.ca)

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AirCare Program Overview

AirCare Program Goals and ObjectivesThe AirCare program is a vehicle emissions inspection andmaintenance (I/M) program. As the name implies, the objective isto inspect motor vehicles to identify those with excessive exhaustemissions and then require that maintenance be performed inorder to lower their emissions output. I/M programs are intendedto complement federal regulations imposed on new vehiclemanufacturers. All new cars sold in Canada since January 1, 1971have been required to conform to federal emission standards.

These standards have been progressively tightened in 1973, 1975,1988, 1994, 1998, and 2002 to the point where emissions from a1998 or newer car are about 2-4% of the levels from anuncontrolled (i.e. 1967) car for hydrocarbons and carbonmonoxide and about 10% for oxides of nitrogen. In 2001, all newvehicles sold in British Columbia were required to meet LowEmission Vehicle (LEV) standards which effectively halved theselevels.

If all of the vehicles sold in Canada in the last 30 years had beenable to maintain the lower levels of emissions as intended for theiruseful lives, there would not be a need to consider I/M programs.

In reality, vehicle defects inevitably occur. In addition to thesedefects, other factors such as lack of maintenance, impropermaintenance, and tampering with emissions controls work againstthe goal of minimizing the impact of the motor vehicle as a majoremissions source.

Vehicles Subject to AirCareUnless exempt, all light-duty vehicles having a GVW of 5,000 kgand under, registered in the Lower Fraser Valley from Furry Creekto Flood require an AirCare inspection prior to re-licensing.

The following vehicles are exempt from the AirCare program:

• Vehicles that are not older than seven model years (for example, for licence renewals in the 2010 calendar year, 2004 and newer model year vehicles do not require an inspection)

• Vehicles with vintage plates or collector plates (except new applications for collector status)

• Farm fleet and agricultural vehicles

• Motor homes with a net vehicle weight over 3500 kg.

• Motorcycles, snowmobiles, amphibious vehicles, ATVs, electric, and hybrid electric vehicles

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Program EnforcementAll vehicles subject to the program must pass or conditionally passan inspection as a condition of licence renewal. Owners of vehiclesthat fail the inspection are required to have repairs performed andthen return to the inspection centre for a re-inspection.

Inspection Centre NetworkThe I/M program concept being used in the Lower Mainlandincorporates "centralized testing" with inspection centres operatedby a contractor.

The network consists of 10 inspection centres and 32 lanes. Eachof the ten inspections centres has two to four lanes, depending onthe population density in the vicinity. No appointment is neededfor an inspection.

Anyone can take a vehicle to the inspection centre as long asproper vehicle identification documents are provided.

Each inspection centre is equipped with at least one all-wheel drivedynamometer. These dynamometers are located in lane one whichis the lane furthest to the left if you are facing the lane entrance.Vehicles equipped with all-wheel drive or traction control aretested on these special dynamometers so as to prevent troublecodes from setting due to differing wheel speeds.

Inspection Centre Locations• Abbotsford: 3380 McCallum Road

• Chilliwack : 45730 Airport Road

• Coquitlam: 1316 United Boulevard

• Langley: 5958 - 205A Street

• Maple Ridge: 11469 Kingston Street

• North Vancouver : 1333 McKeen Avenue

• Richmond: 11115 Silversmith Place

• Surrey: 7910 - 130th Street

• Vancouver East: 3608 Charles Street

• Vancouver South: 728 East Kent Avenue South

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Inspection Procedures

Inspection Frequency

All 1991 and older vehicles are required to undergo annualinspections while 1992 and newer vehicles undergo biennialinspections so long as they pass.

Visual and Functional Inspections

Most vehicles are visually inspected for the presence of a catalyticconverter and a gas cap. Most vehicles up to and including1997model year will also receive a gas cap pressure checkperformed in accordance with the US EPA Technical Guidance. Gascaps are pressurized with a headspace of 1 litre of air at 30 incheswater column. The leakage rate is not to exceed 60 cubiccentimetres per minute (cc/min).

OBD-II Inspections

Eligible 1998 and newer light-duty vehicles receive a scan of thevehicle's built-in OBD monitoring system to ensure there are nodefects with any of the vehicle's emissions control systems.

Exhaust Emission Inspections

1991 and older non-diesel vehicles are tested according to theASM2525 procedure. HC, CO, and NOx are measured while thevehicle is driven at a steady speed of 40 km/hr (25 mph). Themaximum duration of the ASM test is 90 seconds. Emissions arealso measured at idle after the steady-state test.

1992 and newer non-diesel vehicles (up to and including 1997) aresubjected to a more stringent test procedure called the IM240where vehicles are driven at speeds of up to 92 km/hr. Themaximum duration of the test is 240 seconds.

Vehicles equipped with diesel engines will have the opacity of theirexhaust measured under load. All diesel vehicles are tested usinga transient test with speed ranging from 0 - 92 km/hr. The dieseltest is 147 seconds in duration.

Although the primary inspection procedure for 1998 and newervehicles is an OBD-II inspection, in certain circumstances, thesevehicles may receive an IM240 test as a “fallback” test.

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Re-inspections

In most circumstances, inspection centres run exactly the sametests on vehicles being re-tested after repair as on vehicles beingtested for the first time. This ensures that all changes that mighthave occurred during the repair process are recorded.

For more details on re-inspections, see Chapter 14 “Re-inspections” on page 163 of this manual.

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About Pacific Vehicle Testing Technologies

Who Is PVTT?Pacific Vehicle Testing Technologies (PVTT) Ltd. is an operatingsubsidiary of TransLink, the regional transportation authority inMetro Vancouver (formerly referred to as the Greater VancouverRegional District).

PVTT's mandate is to administer the AirCare program. Thisincludes operating the program on behalf of ICBC in the FraserValley. PVTT’s mandate includes:

• ensuring that the inspection contractor is providing consistent and accurate inspections;

• ensuring that effective repairs are available to motorists whose vehicles fail inspection;

• setting the standards for in-use vehicle emissions compliance; and

• monitoring, analysing, and reporting on program effectiveness.

PVTT's Vision"Increased livability through managed mobility"

PVTT's AirCare Mission Statement"To ensure that vehicles which operate in our region continue tooperate with minimum impact on our air quality.”

Our mission will be achieved by:

• Providing accurate, convenient and effective inspections to identify excess emitting vehicles; and

• Providing a competent, challenged and well trained certified repair industry.

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About This Manual

Purpose Of This ManualThis manual is intended to provide certified repair centrepersonnel with a source of reference for everything to do withAirCare.

The chapters on diagnostic procedures are based on over fifteenyears of technicians’ experiences with diagnosing and repairingemissions defects. However, it is important to realize that the largenumber of variables from vehicle to vehicle make it impossible tocover all possibilities in one manual. The best approach is fordiagnostic technicians to arm themselves with as much informationas possible, and to make well-informed decisions wheninterpreting test information and performing component tests tonarrow down the possible causes of excess emissions. Using thisapproach, this manual should be a useful tool for the technician.

For other repair centre staff, the manual should be helpful forclarifying program procedures and policies, and for minimizing thepotential for difficulties in meeting your customer’s needs.

How To Use This ManualThe AirCare Certified Emissions Repair Manual is intended to beused for quick reference on specific topics as needed. It is notintended to be read from cover to cover.

The diagnostic procedures detailed in this manual should be usedas a guide when performing diagnosis of vehicles that have failedtheir AirCare emissions test. When performing component tests,the information provided in this manual should be used inconjunction with manufacturer’s specifications and procedureswhich may be more detailed and more specific to individualvehicles.

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Symbols Used in This ManualYou may come across symbols in the left hand column of thismanual from time to time. The purpose of these symbols is to callparticular attention to an important point. The specific uses ofeach symbol are explained below.

The “FORK IN THE ROAD” symbol means that you can take one of

two paths from where you are now. In the context of proceduralinformation, it means that the next step in the procedure could beone of two entirely different steps. Which path you should takeusually depends on the results of your diagnostic tests up to thatpoint.

The “CRITICAL ERROR” symbol signifies something that iscommonly misunderstood or is a common mistake made bytechnicians. Most automotive technicians have at some point been“burned” by either skipping a step, making an assumption, orsome other type of oversight. The purpose of this symbol is to tryand prevent that from happening to you by calling your attentionto a subject that commonly gets overlooked. It is recommendedthat you read these subjects several times to ensure yourunderstanding. Hopefully this will prevent you from being burnedby one of these common emissions repair oversights.

The “BRIGHT IDEA” symbol is used to call your attention to certain

vehicle defects that have proven to be quite common.

The “CAUTION” symbol is used to call your attention to a situation

that is a potentially hazardous to your personal safety or to thevehicle you are working on.

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About This ManualChapter 1 - Introduction

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Chapter 2AirCare Certification

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Chapter 2 - AirCare Certi f ication

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Certification ConceptInspecting vehicles for emissions can only have a positive effect onambient air quality if the high-emitting vehicles identified in theinspection are competently repaired. In the vast majority of cases,that means complete emissions repairs.

Each motorist whose vehicle fails its AirCare inspection receives alist of AirCare Certified Repair Centres and is encouraged to taketheir vehicle to one of those shops for diagnosis and repairs.

There are two basic incentives for motorists to choose a certifiedshop over a non-certified one:

• First, a repair cost limit may apply to emissions repairs, but only if those repairs are performed by an AirCare Certified Technician at an AirCare Certified Repair Centre. If the needed emissions repairs are costly, motorists have the option of authorizing full repairs if they wish but they are not required to spend more than the repair cost limits. This provides a financial break for the motorist whose vehicle requires costly repairs. The intent is that the vehicle should be completely repaired as soon as the motorist can afford it, and in the meantime, have the highest priority repairs completed.

If repairs are performed at a non-certified shop or by a non-certified technician, there is no limit to the amount of moneythat must be spent in order to pass the inspection.

• Second, upon re-inspection, even if the vehicle’s emissions still exceed the cutpoints, a "conditional pass" is issued. This will occur regardless of how much the repair costs were and regardless of whether the technician identified anything as defective but not repaired. This protects the motorist from the "ping-ponging" back and forth between inspection centre and repair facility that can be common in other programs. If a vehicle receives a conditional pass, the licence and insurance can be renewed.

If repairs are performed at a non-certified shop or by a non-certified technician, a conditional pass cannot occur. The vehiclemust pass the inspection in order to be eligible for re-licensing.

PVTT also provides the RepairNet web site which includes manyresources which can be valuable when diagnosing emissionsfailures. In order to access all of the technical resources onRepairNet, you must be an AirCare Certified Technician and beemployed at an AirCare Certified Repair Centre.

For more information on using RepairNet, see the RepairNet UserGuide (available in the Resources - Manuals section of RepairNet).

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Requirements for AirCare Certification

Repair Centre CertificationShops certified by the AirCare program have indicated they havethe staff and equipment to diagnose emissions defects and toperform effective emissions repairs. Once certified, shops areexpected to abide by the policies and procedures set out by theprogram, and to perform effective emissions repairs.

The program policies and procedures are designed to ensure thatemissions defects are identified and repaired the most efficientway possible. Repair centre certification expires after one year.

Requirements For Repair Centre Certification

The requirements for AirCare Certified Repair Centres are detailedin the document titled “AirCare Certified Repair CentreRequirements“. A copy is included in Appendix E of this manual.

The requirements for AirCare repair centres were drafted with theaid and endorsement of a committee representing the auto repairindustry. These requirements are considered to be what isnecessary to diagnose and repair vehicle defects that cause excessemissions.

For a shop to be certified, the owner or manager must completeand submit an application form to PVTT. The form is titled “RepairCentre Application for AirCare Certification“ and provides PVTTwith details of the business applying to be certified. The facilityowner or manager must also submit a signed copy of a "Code ofPractice" (see Figure 1 “Code of Practice” on page 17).

The signed Code of Practice must be displayed in an area of theshop where it is visible to customers. The Code of Practice showsyour customers that your shop is committed to standards ofservice and customer satisfaction. The Code of Practice is a form ofcontract between the AirCare Certified Repair Centre and PVTT. Asin any contract, failure of one or both parties to abide by the termsrepresents a breach of the contract.

The Code of Practice reflects a new approach to the relationshipbetween PVTT and AirCare Certified Repair Centres. Under thisnew approach, annual visits to the repair shop will no longer occur.Instead, repair centres commit to performing emission-relatedrepairs to the best of their abilities and to standing behind thequality of their work in the event that the customer is notsatisfied. As long as repair centres maintain an acceptablesuccess rate in repairs and customers are not complaining aboutthe service they received, there is really no need for a PVTTauditor to set foot on the premises.

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September 2009

2010

AirCare® Certified Repair Centre Number

CODE OF PRACTICE

AirCare Certified Repair Centre Mission: To achieve emission reductions through a comprehensive and effective repair strategy.

As an AirCare Certified Repair Centre we will:

Perform a thorough diagnosis of your vehicle to identify the root cause(s) of the AirCare failure. Any additional defects that may be recommended for repair, but are not essential to pass the AirCare test, will not be counted towards any applicable repair cost limit.

Provide each customer with a detailed explanation of the required repairs and their estimated cost, and obtain the customer’s authorization before proceeding with the repair.

Ensure an AirCare Certified Technician employed by our facility performs the diagnosis on-site. Repairs may be sublet to specialists or performed by non-certified technicians, but the AirCare Certified Technician is ultimately responsible for the complete repair.

Ensure that the necessary tools and equipment to diagnose and repair emission defects are available and maintained in proper working order.

Choose appropriate replacement parts to achieve maximum emissions benefits. We will use after-market parts if OEM parts are cost-prohibitive.

Provide each customer with a work order or invoice that clearly describes the work performed, and any work still needed to achieve a full pass.

Stand behind our work and resolve all customer complaints in a reasonable and timely manner.

Display this Code of Practice, the AirCare Certified Repair Centre Procedures poster, our AirCare technicians’ Certificate of Endorsement and an official AirCare Certified Repair Centre sign on the premises.

Comply with all AirCare policies and appropriate industry rules and requirements.

Submit repair data to RepairNet for all vehicles prior to re-inspection and provide a copy of the Repair Data Confirmation sheet to each customer.

This AirCare Certified Repair Centre Code of Practice is endorsed by:

a duly authorized representative of: (print name and title)

at

(name of shop) (address of shop)

(signature) M.A. (Martin) Lay, CEO, AirCare

Figure 1: Code of Practice

Requirements For Repair Centre Re-certification

After being certified for one year, shops wishing to be re-certifiedmust submit an application for certification. The application form isidentical to the one submitted for initial certification (see previoussection).

The requirements for re-certification are the same as for initialcertification. However, any outstanding suspensions orunresolved complaints may prevent a repair centre frombeing re-certified.

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Repair Centre Performance Monitoring

To ensure program effectiveness and to enhance public confidence,PVTT staff have identified a number of measures to identifysubstandard performance among AirCare Certified Repair Centres:

• Success rate on re-inspection

• Number of customer complaints

• Number of repair data forms submitted per year

• Calculated REI performance

• Number of calls for technical advice

• Good performance during "mystery shopper" audits

From January 2007, as a condition of Certification, AirCareCertified Repair Facilities have agreed to a Code of Practice whichhas sometimes been described as a performance contract.

Repairs performed in accordance with the Code should be aseffective as reasonably possible within the constraints imposed bythe repair situation, the customer, and other program policies. TheCode also requires that for all AirCare repairs, data will besubmitted to RepairNet before the vehicle is retested.

Performance Indicator Initiated Suspension PolicyPVTT has developed a suite of Performance Indicators (PIs) whichare generated for every AirCare Certified Repair Centre on amonthly basis. The PIs are objective and include the number ofrepairs; the proportions of waivers; records of calls for technicalassistance; customer complaints and resolutions; etc..

One purpose of the PIs is to assist the Performance Review Panelin identifying facilities that are of concern. Each month thePerformance Review Panel creates a short list of facilities whoseoverall performance profile indicates that some remedial actionmay be required.

There are three stages of action. At each stage the PVTT Auditorwill arrange to visit the facility, explain the causes for concern andwhat appears to be required as remediation.

First Visit

At the first visit the Auditor will explain that the facility has beenidentified through the performance review process, and show thedetails of exactly which aspects of performance are of concern.The Auditor will also go through what was previously the standardregular audit, as a first level check to see if there are any obviousproblems which might have caused the performance concern.

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This first stage gives notice to the facility that their performanceappears below average, and that it is now being monitored closelyfor the desired improvement.

Second Visit

After approximately one month the Auditor will make a secondvisit. At this time, if the performance monitoring has shown thedesired improvement, the facility will be removed from the List ofConcern, and the visit is all good news.

If no improvement has been achieved, the Performance ReviewPanel will create a list of reccommended actions that it believeswould address the problem, and at this second visit the Auditorwill inform the facility what these actions are. However, it will beentirely up to the facility to decide what remedial actions it willactually take.

During this second stage, the facilities performance will continueto be monitored very closely.

Third Visit

Approximately one month later the Auditor will make a third visit.Again, if the performance monitoring has shown the desiredimprovement, the facility will be removed from the List of Concern,and the visit is all good news.

If no improvement, or inadequate improvement, has beenachieved, the facilities ability to issue conditional passes will besuspended for a period of three months. The Auditor will post aNOTICE TO CUSTOMERS adjacent to the AirCare Certified RepairCentre Procedures poster. The purpose of the suspension is toprovide more time for the facility to address the problems whichhave caused poor performance.

During the suspension the facility will still be able to submit repairdata to RepairNet, but only to facilitate performance monitoring byPVTT. All of the repair data submitted during the suspension will bemonitored, but it will not be possible for a vehicle to obtain aconditional pass on the basis of the data.

At the end of the suspension, the facility will continue on the Listof Concern. If, after one month, the facilities performance hasimproved enough, they will be removed from the List of Concern.However, if performance continues to be unacceptably poor,another three month suspension will be initiated.

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Technician Certification

Requirements For Technician Certification1) British Columbia Trades Qualification (BCTQ) or Certificate of

Qualification in either:

• automotive mechanical repair;

• heavy-duty mechanical repair with at least three years automotive experience; or

• commercial vehicle mechanical repair, or:

British Columbia Certificate of Apprenticeship in auto electricand tune-up.

2) Demonstrated knowledge of how to diagnose emissions defects and to perform effective emissions repairs, either by success-fully challenging a written, 3-hour examination or by maintain-ing a good record of success over a minimum of one year of performing AirCare repairs and submitting repair data.

Once certified, technicians are expected to abide by the policiesand procedures set out by the program, and to perform effectiveemissions repairs. The program policies and procedures aredesigned to ensure that emissions defects are identified andrepaired the most efficient way possible.

At the moment, all AirCare Certified Technicians are set to havetheir certification expire on December 31, 2011.

Requirements For Re-instatement & New Technicians

Technicians who have allowed their AirCare certification to lapse ornew technicians entering the trade who wish to be certified mustsatisfy the two basic requirements described in the previoussection.

Qualifying examinations are currently being administered by theAutomotive Training Standards Association. Technicians wishing toregister to write the exam must make arrangements with theAutomotive Training Standards Association and show proof thatthey hold a valid trades qualification certificate prior to beingallowed to write the exam. The exam consists of 100 questionsand the minimum passing grade is 70%. Technicians whosuccessfully meet the requirements will be certified until December31, 2011.

Fuel Type Endorsement

Technicians are certified for one or more fuel types. To be certified,a technician must pass the section of the examination that is

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specific to that fuel type. The alternate fuel type endorsement alsorequires that the technician possess a gas-fitter certificate.

Technicians must not perform AirCare repairs on vehicles that areof a fuel type they are not certified for. This includes dual-fuelvehicles even if running on gasoline when they failed the AirCareinspection. If a vehicle has an alternative fuel system installed,you must have the AC or GA fuel type endorsements to do AirCarerepairs on it.

Technician Identification Cards

Technicians are issued a plastic identification card after passingthe qualification exam. The ID card uniquely identifies eachcertified technician with a six digit technician number followed bya computer generated “check digit” for security.

WHAT IF I LOSE MY

ID CARD?If the card is lost or destroyed, the technician must immediatelynotify the PVTT certification department at 604-453-5152. Adeclaration form must be completed and sent to PVTT’s officebefore a replacement can be ordered.

Technician Responsibilities

What Is Expected Of The Technician

As an AirCare certified technician, you are expected to:

• correctly and efficiently identify the emission defect(s) of each failing vehicle that you have been authorized to diagnose;

• exercise good judgement when prioritizing and estimating repairs;

• ensure that the results of your diagnosis are clearly communicated to your customer;

• ensure that the options your customer may have regarding authorizing and completing repairs, and the results that should be expected, are clearly communicated to your customer;

Table A: AirCare Certified Technician Fuel Type Endorsements

Fuel Type Endorsement Abbreviation

All Categories AC

Gasoline Only GL

Gasoline / Alternate GA

Gasoline / Diesel GD

Diesel Only DL

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• follow good trade practices when performing repairs after you have obtained the appropriate authorization from your customer; and

• accurately enter the results of your diagnosis and repair on RepairNet.

What Is Beyond The Control Of The Technician

The repair cost limit system provides some motorists with anoption of not authorizing completion of all repairs. If a customerchooses not to authorize completion of all needed emissions repair,it is beyond the control of the technician. In these circumstances,it is to be expected that the vehicle will perform worse thanaverage upon re-inspection.

Also, to a large extent, the cost of parts is beyond the control ofthe technician. In many cases replacement parts may be availablefrom a variety of sources and with a wide range of prices. Allavailable options should be explored but if parts are costprohibitive, obviously that is not the technician’s fault.

The Repair Effectiveness IndexThe Repair Effectiveness Index or “REI” is an analysis thatevaluates each repair. An average of all REIs over a period of timecan be statistically significant as an objective measure oftechnician and repair centre performance.

The REI is used by PVTT for the following purposes:

• to provide timely feedback, to help technicians develop a sense of how effective their repairs have been;

• to identify an industry average;

• to identify and officially recognize technicians achieving the best results; and

• as one of the performance indicators that may contribute to a decision to audit a certified repair facility.

The Logic Of The REI

Basically, the greater the improvement between the “before”situation and the “after” situation, the more effective the repair.However, the formula for calculating REI is quite complex as ittakes into consideration many variables including the before-and-after, what the vehicle is capable of, whether the repair cost limitswere a limiting factor in the repair, and whether the technician’sdiagnosis was accurate. Each aspect of the REI is explained in thischapter.

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A new, additional formula for REI was introduced in January 2007in order to deal with OBD inspections. This formula considers theOBD results, the readiness monitors, and the number of diagnostictrouble codes.

REI for Tailpipe Inspections

The REI is the sum of three key factors relating to how accuratelyan emissions failure was diagnosed and how effectively it wasrepaired. The final REI will be a number ranging from 0.00 to10.00. The higher the number the better.

The three key factors are referred to as V1, V2, and V3. However,the three values are not of equal relevance. V1 and V2 aresignificantly more important than V3 and are weighted accordingly.More specifically, the V1, V2, and V3 measures are not equal thirdsof the final REI but rather, 42%, 42%, and 16% respectively.

The easiest way to understand the REI calculation is to look at thepurpose of each of the three measures.

V1: Difference Between Before and After Readings

Obviously an effective emissions repair will reduce a vehicle’semissions. The greater the reduction, the more effective the repairwas.

When emissions are measured twice using a highly controlled testprocedure, a reasonable comparison can be drawn between eachmeasurement. The V1 aspect of the REI totals each emission fromeach test mode and compares that total with the re-inspectionresults.

The V1 value makes up 42% of the final REI.

V2: What Vehicle Is Capable Of

The most effective repairs will result in vehicle emissions being at,or very near, a normal level.

To evaluate whether a vehicle’s emissions are at or near a normallevel, the V2 aspect of the REI compares the total of emissionsfrom each test mode with the average emissions for all passingvehicles of the same type.

The V2 value makes up 42% of the final REI.

V3: Diagnostic Conclusions and Repair Items

The accuracy and completeness of the technician’s diagnosis isalso an important part of the repair effectiveness picture. Differentcombinations of repair data and re-inspection results can indicate

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substantially different degrees of repair effectiveness. One of thefollowing scenarios will apply:

• If nothing is indicated as defective but not repaired, the vehicle should be emitting at or near normal levels when it is re-inspected. If the vehicle passes the re-inspection, this indicates that the diagnosis was accurate and complete. In this scenario the V3 will be 10.00.

• If nothing is indicated as defective but not repaired, but the vehicle doesn’t pass re-inspection, the technician either overlooked something or did something incorrectly. As a technician, you can’t get any less effective than this. When re-inspected, the vehicle will still be conditionally passed but will be categorized as a qualifying waiver or “Q” waiver. In this scenario V3 will be 0.00. For info on remedying this low REI see “Second Chance REI” on the next page.

• If one or more items are indicated as defective but not repaired and the vehicle doesn’t pass re-inspection, this is also not an effective repair. However, because of the repair cost limit, this result is not the technician’s fault. Upon re-inspection, the vehicle will receive a conditional pass and be categorized as a cost waiver or “C” waiver. V3 will be 5.00 for all C waivers.

• If certain items are indicated as defective but not repaired and the cost limit was high enough that they could have been repaired, that also is a very ineffective repair. V3 will be 0.00 if this happens.

• If re-inspection results are indicative of a vehicle running normally (all readings good enough to fast-pass) yet the repair data shows a major emissions repair item as being defective but not repaired, this indicates that the diagnosis was inaccurate. In these circumstances V3 will be 0.00.

For a given re-inspection, only one of the above V3 scenarios willapply. The V3 value makes up 16% of the final REI value.

REI for OBD Inspections

An OBD inspection does not provide tailpipe emissionconcentrations or mass emissions. So, the OBD-based REI dependson three factors which are provided by an OBD inspection.

• Was the MIL commanded ON or OFF at the time of reinspection? A vehicle returning with the MIL commanded ON is naturally given a much lower REI.

• How many DTCs were reported with the initial failed inspection? More REI credit is given for more initial DTCs.

• How many Readiness Monitors were not ready at the time of reinspection? Having monitors still not ready reduces the REI.

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Second Chance REI

In the event that a vehicle you have worked on comes back to youafter getting an unexpected conditional pass on re-inspection, andyou then complete the repair, you can still get credit towards yourREI.

To get REI credit for this second chance repair, just submit anotherRepair Data Form on RepairNet following completion of thenecessary repairs, before the vehicle returns for another re-inspection.

Individual REI vs. Average REI

An REI is calculated for each diagnosis/repair that is performed.REIs for each repair performed in a 12-month period are averagedto arrive at the technician average REI, and the repair centreaverage REI.

Assuming a reasonable number of vehicles have been diagnosed/repaired, an average of all REIs over a period of time can bestatistically significant and an objective indicator of technician andrepair centre performance.

Shops and techs can view their individual REIs and their averageREI over the previous 12-month period on RepairNet by selecting“User Info” and “Your Repair Record”.

REI Implications

Quality Repair Awards

Technicians with exceptionally high REIs over a quarterly periodreceive the AirCare Quality Repair Award. The award criteria isperiodically updated based on industry averages.

Currently the Quality Repair Award criteria is:

• an REI of 8.00 or higher for 13 - 24 repairs

• an REI of 7.75 or higher for 25 or more repairs

A certificate recognizes the achievement of Quality Repair Awardwinners. Recipients also receive AirCare branded rewards.

Three-time winners of the Quality Repair Award receive a specialwooden wall plaque to recognize their achievement as well as afree lunch for the staff at their work location.

P.A.L.M. Program

Technicians that obtain Quality Repair Awards are furtherrecognized as superior technicians by the PALM program. The

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designations under the PALM program are shown below along withthe criteria:

• Pioneer (1 Quality Repair Award received)

• Achiever (3 Quality Repair Awards received)

• Leader (6 Quality Repair Awards received)

• Master (10 Quality Repair Awards received)

Performance Review

Average REIs for each facility and technician are also compared tothe industry average REI. Unacceptably low performance may because for performance review and facility audit.

What Causes Mid-Range Average REIs

An REI of 5.00 is mid-range and, for tailpipe-tested vehicles, itessentially means that there was no emission reductions achievedfollowing repairs. Each repair that results in no improvement inemissions will result in a V1 value of 5.00. Too many of these andyour average REI for the quarterly period will be low as well.

For OBD vehicles, mid-range REI values can result from the MILstill being commanded ON at reinspection, or a number ofmonitors not being ready.

How Mid-Range Average REIs Can Be Prevented

Here are some things you can do to prevent a low average REI:

• Make sure your gas analyzer is properly calibrated and leak-checked on a regular basis.

• Ensure that whoever is responsible for customer communications is clearly conveying what repairs are required and what are optional along with the benefits of completing those repairs.

• After you have completed an OBD repair, try to ensure that all the monitors have a chance to complete before re-inspection. This may mean letting the customer drive the vehicle for a few days, then checking its OBD status again before it goes for re-inspection. For more details, see “Preparing the Vehicle For Re-inspection” on page 78.

• If you are having difficulty with diagnosis, re-read Chapters Chapter 3 through Chapter 8 of this manual.

• If you are still having difficulty with diagnosis, call the techline.

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What Causes Sub-Par REIs

If a lack of improvement in vehicle emissions causes mid-rangeREIs, then a sub-par REI must mean that emissions have actuallyincreased. However, this is not a likely scenario unless there areother over-riding factors.

There are four circumstances that may (depending on otherfactors) result in a sub-par REI:

1) Your diagnosis is incomplete (Q waiver);

2) You applied the repair cost limit incorrectly (a needed repair is not completed even though it could have been done within the repair cost limit);

3) You indicated that a major emissions defect exists (one that would adversely affect emission levels), yet the vehicle per-formed well on the re-inspection; or

4) An OBD vehicle was re-inspected with the MIL still commanded ON, and before the monitors had completed

A sub-par REI is not only the worst result that you can get, it alsoreduces your average REI. To achieve a good average REI youmust not allow any sub-par REIs to occur.

How Sub-Par REIs Can Be Prevented

A sub-par REI is the result of an incomplete or inaccuratediagnosis, or of not making any effort to ensure OBD monitors arecomplete. The obvious way to prevent a sub-par REI is to do acomplete and proper diagnosis of every AirCare failure, tocorrectly apply the repair cost limit, and to always ensure thatOBD Readiness Monitors have completed.

As an AirCare certified technician, you should be aware thatmeasuring a vehicle’s emissions at idle and 2500 does notconstitute a complete and proper diagnosis. However, technicianswho get sub-par REIs often have that misconception.

If you are not able to identify the defect, the right way to handlethe situation is to double-check your diagnosis to make sure youhaven’t overlooked anything and then call the techline for

assistance. The wrong way to handle these situations is toconclude that there is nothing wrong with the vehicle and to sendthe motorist back to the inspection centre for a re-inspection.

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Technician Performance Monitoring

To ensure program effectiveness and to enhance public confidence,PVTT staff have identified a number of measures to identifysubstandard performance:

• Success rate on re-inspection

• Number of customer complaints

• Number of repair data forms submitted per year

• Calculated REI performance

• Number of calls for technical advice

• Good performance during "mystery shopper" audits

Not all of the performance parameters listed above can beexpressed in a purely numerical form, thereby requiring somedegree of of qualitative evaluation. Although the new system isstill in its infancy, the goal is to combine numerical indices withqualitative data to identify candidates for further investigation.

PVTT will visit repair shops and technicians that appear to beunder-performing in order to identify possible causes. For moredetails, see “Performance Indicator Initiated Suspension Policy” onpage 18.

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Chapter 3Vehicle Inspection Report

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Chapter 3 - Vehicle Inspection Report

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Purpose of the VIRThe Vehicle Inspection Report (VIR) documents the result of eachAirCare inspection performed. It is printed and given to themotorist upon completion of each inspection. This sectiondescribes what appears on the VIR and what it means.

Figure 2: Vehicle Inspection Report (VIR)

If the vehicle fails inspection, the motorist will also receiveanother document which provides further detail of the vehicle’semissions performance during the test (see “Diagnostic TraceReport” on page 43).

Thanks for doing your part for clean air! Since 1992, your efforts have reduced vehicle emissions by 76%.

INSPECTION RESULTS

EXHAUSTEMISSIONS

ON BOARDDIAGNOSTICS

GAS CAPPRESENCE

GAS CAPPRESSURE

CATALYTIC CONVERTER PRESENCE

FINALRESULTAMOUNT PAIDTEST TIMETEST DATE

AIRCARE EXPIRY

DATEREGISTRATIONNUMBER

VEHICLE YEAR

VEHICLE MAKE

VEHICLE TYPE

ENGINESIZE

ODOMETERREGISTEREDCURB WEIGHT

VEHICLE IDENTIFICATIONNUMBER (VIN)

VEHICLE INFORMATION

ON BOARD DIAGNOSTIC TEST DIAGNOSTIC INFORMATION

,000

DRIVING TEST

YOUR CO2 CALCULATION

MAXIMUMALLOWABLE

VEHICLEREADING

AVERAGE PASSINGREADING RESULT

RESULT

IDLE TESTMAXIMUM

ALLOWABLEVEHICLEREADING

AVERAGE PASSINGREADING RESULT

FUEL CONSUMPTION(LITRES PER 100 km)

FOR MORE INFORMATION ON YOUR AIRCARE TEST, SEE REVERSE OR VISIT www.aircare.ca FORM #7002 REV 06/2008

Vehicle Inspection Report

DISTANCE DRIVEN(,000 km PER YEAR)

CO2

(TONNES PER YEAR)

LEAST AVERAGE MOST 0 10 20

LEAST AVERAGE MOST 0 16 30

BEST TARGET AVERAGE WORST 0 (2.7) 4 8

=+

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Emissions Standards

Tailpipe Testing StandardsThe maximum allowable emission levels (also known as cut-pointsor standards) used in the AirCare tailpipe inspection are used toidentify excess emitting vehicles. But how do you defineexcessive?

Most importantly, the emissions standards used in the AirCareprogram are based on the level of emission control technology thatthe vehicle was built with. This level of technology was based onthe federal emissions standards in place when the vehicle wasproduced. Since their introduction in Canada in 1971, these federalstandards have been progressively tightened.

WHAT ABOUT OLD VEHICLES?

With regard to vehicles produced prior to any federal emissionsstandards the AirCare emissions standards are based on the basicchemistry of combustion. As such, any pre-emission controlvehicle, from a Model T to a dual-quad hemi, should pass thesestandards, provided that the engine and its fuel and ignitionsystems are correctly calibrated and functioning properly.

WHAT ABOUT HIGH-MILEAGE VEHICLES?

Another important consideration in setting in-use vehicleemissions standards is to allow for normal variation anddegradation in emissions levels. Some may be surprised to knowthat emission levels do not increase by a large amount as a vehicleages. An engine can have hundreds of thousands of kilometres onit and still be nearly as clean as when it left the factory. This isparticularly true of vehicles manufactured with a catalyticconverter.

What does result in significant increases in emission levels aredefects. Lazy catalytic converters, tired and worn-out O2 sensors,worn metering rods and jets, engine mechanical defects, etc.

It is extremely important to understand that the AirCare standards

are not "specifications" that indicate an optimum condition. Don’tget caught by the misconception that if the reading is below theAirCare emissions standards everything is okay. This is notnecessarily the case. The AirCare standards are used solely for thepurpose of identifying a vehicle that is polluting well beyond whatit would be if operating as designed.

AirCare tailpipe testing standards are prescribed in the MotorVehicle Act Regulations BC Reg 274/2000 - Exhaust EmissionsStandards Regulation.

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On-Board Diagnostic Testing StandardsCurrently, most I/M programs in North America are moving fromtraditional dynamometer based tailpipe testing to On-BoardDiagnostic (OBD) inspection scans for newer vehicles. In the U.S.,all 1996 and newer light-duty vehicles are equipped with OBD IItechnology. In Canada, OBD II became mandatory in 1998.

The OBD system continuously checks the operation of keyemissions control components and emissions-related systems in avehicle. If the OBD system detects a fault that could causeemissions to exceed the applicable federal new vehicle standardfor any pollutant by 50% or more, the dashboard MalfunctionIndicator Lamp, or MIL, will be illuminated.

For eligible 1998 and newer vehicles receiving an OBD non-tailpipeinspection, the emission standard is:

1) the motor vehicle is fitted with an operative data link connector;

2) fewer than 2 readiness monitors in the motor vehicle have a Not Ready status when the onboard emissions diagnostic device is interrogated; and

3) the malfunction indicator lamp is not commanded on by the onboard emissions diagnostic device.

The above criteria is prescribed in BC Motor Vehicle Act Regulation40.051.

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Detailed Explanation Of The VIRThis section provides details on the information that can be foundon the Vehicle Inspection Report (VIR). This information will besomewhat different depending on test type and final result.

Inspection ResultsThe first section of side one of the VIR shows general inspectioninformation including the date and overall result of the test. Inaddition to the overall result, you can see the pass/fail result foreach applicable part of the inspection;

• On Board Diagnostics - the result of the OBD portion of the inspection.

• Exhaust Emissions - the result of the tailpipe sampling portion of the inspection.

• Catalytic Converter Presence- the result of the visual inspection for the presence of a catalytic converter.

• Gas Cap Presence - the result of the visual inspection for the presence of a properly fitting gas cap.

• Gas Cap Pressure - the result of the functional inspection of the gas cap.

In order for the Final Result to be pass, the vehicle must pass eachpart of the inspection that applies to that type of vehicle.

Vehicle InformationThe Vehicle Information section provides details of the vehicle thatwas inspected;

• Registration Number - this number is a seven-digit number that identifies the vehicle in ICBC’s database. The registration number remains assigned to the vehicle regardless of ownership transfers and licence plate changes.

• Vehicle Year - the model year as shown on the vehicle registration record.

• Vehicle Make - the manufacturer of the vehicle as shown on the registration record.

• Registered Curb Weight - the curb weight or net weight in kilograms (kg) as shown on the vehicle’s registration record.

• Vehicle Identification Number (VIN) - the unique identification number assigned by the manufacturer.

• Vehicle Type - the body style of the vehicle (passenger car or truck).

• Engine Size - engine displacement in litres.

Detailed Explanation Of The VIRChapter 3 - Vehicle Inspection Report

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• Odometer - the vehicle’s odometer reading at the time of inspection.

• AirCare Expiry Date - the last day that the vehicle is eligible to be re-licensed. Note that this date is different from the expiry date of the vehicle’s licence and insurance policy.

On Board Diagnostic TestThe On Board Diagnostic test section provides details for:

• MIL Engine Off (KOEO - Key On Engine Off)

• MIL Engine On (KOER - Key On Engine Running)

• Diagnostic Link Connector Tampering

• OBD II Communications

• MIL Command Status.

The OBD portion of the VIR also contains a section for DiagnosticInformation, which displays the status of the vehicle's ReadinessMonitors and lists any Diagnostic Trouble Codes that wereidentified by the vehicle’s OBD system.

Driving TestDriving Test refers to the portion of the inspection that uses adynamometer to simulate normal driving conditions. For eachdriving test, the load application and duration of the test isautomatically controlled by the computer.

The Driving Test section contains the detailed results for eachmode of the test where the tailpipe emissions were measured.

For each regulated pollutant, the VIR will show the following:

• Units of Measure - the column to the left identifies each measured pollutant and the units of measure in parts per million (ppm), percent (%), or grams per kilometre (g/km).

• Average Passing Reading - this is the average reading for other vehicles of the same type that passed inspection. This statistic is useful as a point of reference for what the vehicle is capable of.

• Vehicle Reading - this is the actual emission level for the vehicle at the time of the test.

• Result - this is the pass/fail result for the particular pollutant and test mode.

• Maximum Allowable - this is the actual emission standard or “cutpoint” that is applicable to the particular vehicle. The standards are prescribed in the Motor Vehicle Act Regulations (B.C. REG. 274/2000 - Exhaust Emission Standards Regulation).

The driving test may be one of the following depending on modelyear and fuel type;

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ASM2525 • ASM2525 - this driving test applies to 1991 and older non-diesel vehicles. The ASM driving test is a steady-state operating condition where the vehicle speed is held at 40 +/- 1.6 km/hr at a load simulating an uphill grade of approximately 3%.

The test will last from approximately 30 seconds to 90 secondsdepending on emission levels. If the vehicle being tested isexhibiting emission levels well below the cutpoints the test willterminate relatively quickly. This is known as a fast-pass.

The results printed on the VIR will be the average of theemissions measured over the final ten seconds of the test mode.

IM240 • IM240 - this driving test applies to 1992-1997 non-diesel vehicles. The IM240 driving test is a transient test that includes accelerations and decelerations as well as cruise and idle conditions. The vehicle speed must closely follow a trace derived from the EPA75 federal test procedure.

The test will last from approximately 30 seconds to 240 secondsdepending on emission levels. IM240 inspections with a durationof less than 240 seconds are known as fast passes. For adetailed description of IM240 fast passes, read the 2002-1 issueof the AirCare Repair newsletter.

D147 (DIESELS ONLY) • D147 - this test applies to diesel vehicles only. The driving test is a transient type of test that includes accelerations and decelerations as well as cruise conditions. The vehicle speed must closely follow a trace that is derived from the EPA75 federal test procedure. The test will last from 97 seconds to 147 seconds for all vehicles tested using the D147.

NOTE: Regardless of the type of test used, the test duration willalways be the maximum if the result is fail.

Idle TestIdle Test refers to the portion of the inspection where emissionsare sampled while the vehicle is idling. Only CO and HC standardsare applicable to the idle test.

The idle test mode follows the ASM mode on 1991 and oldervehicles. It is also used for vehicles of any model year in rarecircumstances where the vehicle cannot undergo a driving test.

During the idle test, after pre-conditioning has occurred and theengine has stabilized at normal idle speed, the vehicle’s emissionlevels are compared to the applicable standard. The vehiclereadings and maximum allowable levels are printed on the VIRalong with average readings for vehicles of the same type thatpass inspection.

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What You Can Learn From The VIRAs well as being a record of the inspection results for the motorist,if the vehicle has failed inspection, the information on the VIRprovides the starting point for diagnosis of the defect.

From a diagnostic point of view, the information on the VIR shouldalways be considered before attempting any diagnosis of thevehicle. Given the vehicle year and emission readings, in mostcases the technician should be able to identify the area that shouldbe given highest priority for component testing.

For example, a VIR showing ASM results for a late model vehiclewith HC, CO, and NOx readings that are typical of engine-outconcentrations indicates that the vehicle likely has a dead catalyticconverter. Logically, testing the catalytic converter should be thehighest priority in your diagnosis.

As another example, a VIR showing idle test results for an oldervehicle with excessive CO likely indicates that the idle air-fuelmixture is out of adjustment. However, if you observe on youranalyzer that the CO is within normal range this indicates the richcondition is intermittent or erratic. The focus of your diagnosisshould be on those items that can cause erratic fuel deliveryproblems (e.g. carburetor float, sticking PCV valve, sticking powervalve or metering rods, etc.).

In some cases, the information on the VIR may not provide a clearpriority for which component or components should be tested.However, the technician should be able to determine whetheradditional inspection details will help to formulate a diagnosticstrategy.

For example, a VIR showing IM240 test results with failing NOxlevels but also higher than average CO and HC could indicate acatalytic converter problem. However, it also could indicate a fuelcontrol problem. In this case, more detailed inspection resultswould be useful to see how the vehicle performed throughout theinspection. That would help to narrow down the likely cause of theproblem. Fortunately, more detail is provided on the DiagnosticTrace Report (see Chapter 5 “Diagnostic Trace Report” on page 43)and the Second-by-Second Reports (see “How To Read the SecondBy Second (SBS) Reports” on page 60).

For more details on how to interpret the VIR for diagnosticpurposes, see “Review Inspection Results” starting on page 90.

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What You Can Learn From The VIRChapter 3 - Vehicle Inspection Report

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Chapter 4Detailed Inspection Data

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Chapter 4 - Detai led Inspection Data

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Types of Detailed Inspection Data Available

Detailed Emissions DataAs you probably know, it is not uncommon for a vehicle to have anemission defect without any other obvious symptoms. Not onlythat but many emissions defects result in erratic emissionsperformance so that failing vehicles may at times emit normalemission levels. This is particularly true with late model vehicleshaving more advanced emission control technology. For this reasonit is important that the diagnostic technician have the ability toevaluate detailed emissions data that was captured at the time ofthe test failure.

When a vehicle receives an IM240, ASM, or D147 emissions test,emissions data is captured for each second of the test. That data isreferred to as Second-By-Second (SBS) data.

Detailed Data For Other TestsIn addition to SBS data, other detailed data is available for OBDtests, and even for aborted tests. Collectively, this type ofinformation is referred to as Detailed Inspection Data or, onRepairNet, simply Detailed Data.

OBD Tests

For vehicles receiving an OBD test, the Detailed Data includesidentification of specific Diagnostic Trouble Codes (DTCs), and thestatus of all applicable Readiness Monitors. Readiness Monitorstatus is also available for aborted OBD tests.

Aborted Tests

Aborted tests are a unique situation because the test wasn’tactually completed. However, more details about why the testcould not be completed can be found under Detailed Data onRepairNet.

Types of Detai led Inspection Data AvailableChapter 4 - Detai led Inspection Data

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Sources of Detailed Inspection DataWhen a vehicle fails an IM240, ASM, or D147 inspection, they willreceive a document called the Diagnostic Trace Report (DTR) alongwith the VIR. The DTR includes graphical representations of SBSdata for each measured emission. For more detail on the DTR,refer to “Diagnostic Trace Report” on page 43.

As well as the DTR, SBS data is available on RepairNet in bothgraphical and tabular form. Whether you prefer to view SBS datain a line graph or a table is a matter of personal preference. Forinspections where SBS emissions measurements are captured, thedata can be accessed on the AirCare Inspection History page. Formore details on using RepairNet, see the RepairNet User Guide.

Comparing the sources of SBS data (the DTR and RepairNet),several of the reports are quite similar, however, it is important torealize the differences and advantages of each. Table 2 lists thesesources and their respective characteristics.

In Table 2, the phrase “raw measurements” means that the data isprovided as measured (no calculations applied). Conversely,calculated data refers to data that is an estimate of the actualconcentrations.

For more information on how to use SBS data including examples,see “Diagnostic Trace Report” beginning on page 43 and“Obtaining Additional Diagnostic Information” beginning onpage 57.

Table 2: Comparison of SBS Emissions Inspection Data Available to Technicians

Report Name Source of Report Type of Data Source of Data Advantage

IM240 DTR Inspection Centre graph raw measurements raw measured data

IM240 SBS Graph RepairNet graph calculated bigger graph

IM240 SBS Table RepairNet numerical calculated numerical data

ASM DTR Inspection Centre graph raw measurements

ASM SBS Graph RepairNet graph raw measurements bigger graph

ASM SBS Table RepairNet numerical raw measurements numerical data

Idle SBS Graph RepairNet graph raw measurements only graph for idle test

Idle SBS Table RepairNet numerical raw measurements numerical data

D147 DTR Inspection Centre graph raw measurements

D147 SBS Graph RepairNet graph raw measurements bigger graph

D147 SBS Table RepairNet numerical raw measurements numerical data

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Chapter 5Diagnostic Trace Report

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Chapter 5 - Diagnostic Trace Report

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Purpose of the DTRThe Diagnostic Trace Report (DTR) provides a graphicrepresentation of the individual emission levels throughout theduration of the test. This information can be useful in diagnosingthe cause of an emissions failure.

This section provides details on the information that can be foundon the DTR and how that information can be helpful in arriving at adiagnostic conclusion.

Figure 3: Diagnostic Trace Report (DTR)

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DIAGNOSTIC TRACE REPORTRepair decisions should not be made based solely on this report.Please be sure to take this report along with your AirCare Vehicle InspectionReport to your repair technician.

OEmissions

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FOR OFFICE USE ONLY

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Purpose of the DTRChapter 5 - Diagnostic Trace Report

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Detailed Explanation Of The DTRFor vehicles that fail an ASM, IM240, or D147 inspection, the DTRprovides a separate graph for each measured emission over thecourse of the test. The graphs display the emission level on thevertical (y) axis and time on the horizontal (x) axis. The range ofthe y axis (emission levels) is printed on the left side of the graphand will be different from test to test. This is because it is basedon the peak emission levels recorded during the test. In otherwords, it has to be scaled so that the highest emission peaks canfit on the graph. If the emission levels appear to dip below thezero line, it is probably because the alignment of the page in theprinter was off a little bit.

Figure 4: Driving Trace For Each Type of Dynamometer Test

For IM240 inspections, individual graphs are shown on the DTR forHC, CO, NOx, and CO2. For ASM inspections O2 is shown as well.For D147 inspections, a DTR graph is shown for opacity only.

A Drive Trace graph at the bottom of the page shows the threedynamometer driving traces that are used (see Figure 4). This isused as a point of reference so you can see what sort of operatingcondition the vehicle was at for each second of the test.

For failed IM240 inspections, the DTR graphs will use the entirewidth of the graph area because the test will have been 240seconds in duration. For failed ASM inspections, the emissionsgraphs will only use the first 90 seconds of the time axis becausethat is the full duration of that test mode (the red dotted line thatfollows represents the idle test). Similarly, D147 tests will only use147 seconds on the time scale.

In most cases, emissions will initially be high at the start of thetest and then decrease as the catalyst efficiency increases. You willbe able to see how long it took for the catalyst to begin to beeffective (if at all). Tired or lazy catalytic converters and oxygensensors can sometimes be detected by looking at the emissionlevels at the beginning of the IM240 driving test and how quicklythey decrease as the test continues.

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Using The DTR To Assist Your Diagnosis

IM240 DTRs

HC, CO, NOx, and CO2 emissions appear on the DTR in theirmeasured units—grams per kilometre. Oxygen levels are notmeasured during an IM240 inspections so they will not appear onthe DTR.

For IM240 DTRs, it is best to look at the DTR in conjunction withthe second-by-second readings which are always shown in percentand parts per million. See “How To Read the Second By Second(SBS) Reports” on page 60. However, you should remember thatparts per million and percent readings for IM240 inspections arederived using a reverse dilution calculation. Because of the widelyvarying exhaust flow during a transient test, these derivedreadings won’t always be as accurate as the grams per kilometrereadings.

On the DTRs you will often see spikes in emission levels at thevarious points of the test where the vehicle is accelerated anddecelerated. If you see a large variation in the HC and CO levels atvarious points of the test, it could be due to an intermittent loss offuel control. However, substantial spikes are normal at certainpoints of the test because low distance travelled and high exhaustflow add up to high grams per kilometre.

Another common fault that is often evident in the IM240 DTR is aweak catalytic converter. Weak catalytic converters are sometimesable to do an adequate job of reduction and oxidation under lowexhaust volume conditions such as idle and light loads, but are notup to the task under higher exhaust flow conditions and higherloads. This can be evident in the emissions levels at the points ofthe test where the vehicle is accelerated briskly, and at the pointwhere the vehicle is cruising at highway speed. Be sure to look atboth of these high exhaust flow areas because high emissionsduring acceleration could be due to normal enrichment, but thefuel control should definitely be in closed loop and emissions lowduring highway cruise conditions.

IM240 DTR Examples

In Figure 5, Figure 6, and Figure 7 on the following pages, someexample IM240 DTRs are provided. The DTR shown on page 49 isfor a 1992 4.0L vehicle that passed the inspection but received afull duration (240 second) test even though it was clean enough tofast-pass. Because every DTR that you see in the field will be froma vehicle which has failed inspection, this DTR may be particularlyuseful to you. It is a good DTR to use for comparison with DTRsfrom failing vehicles.

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In Figure 6 on page 50 an IM240 DTR is shown for a vehicle with aMAF sensor that is under predicting air flow at high speed. InFigure 7 on page 51, an IM240 DTR from a vehicle with a leakingcentral injector is shown. There are a number of things to takenote of in these DTRs:

• The most important thing to understand is that you should not attempt to diagnose a vehicle based on the DTRs alone. You should always use this information in conjunction with all of the available information and component level testing to pinpoint the defect.

• The first thing to look at on the DTRs is the scale shown at the left for the individual graph. The scale is different for each inspection and each graph because the system will automatically pick the most appropriate size for graphing the data. For a good example of how the scale can change how a graph looks, see Figure 12 and Figure 13 on page 56.

• In the DTR graphs shown in Figure 7, the HC and CO graphs are both scaled very high and the levels are high throughout the test. This suggests a very rich mixture under all operating conditions.

• The emission levels should be evaluated in relation to the vehicle operating conditions and in relation to each other. For example, in Figure 6 the NOx and CO2 increase sharply at the point of acceleration to highway speed (approximately 160 seconds into the test) but CO doesn’t. Given that this is a fairly major acceleration, this indicates a lack of adequate enrichment. About ten seconds later, the CO finally spikes up—probably due to a long term fuel trim adaptation. The same thing that caused this lean condition (in this case a dirty MAF sensor) was preventing the catalyst from reducing NOx.

• The traces for CO2 on all three examples are at similar scales and have similar peaks—even Figure 5 where the vehicle is running normally. This is because each of these vehicles are similar in weight and engine size. CO2 is the best indicator of exhaust volume.

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Figure 5: IM240 DTR - 1992 4.0L Light-Duty Truck Running Normally

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Figure 6: IM240 DTR - NOx Failure Due To Dirty MAF Sensor

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Figure 7: IM240 DTR - CO and HC Failure Due To Leaking Injector

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ASM DTRs

HC, CO, NOx, CO2, and O2 are measured during an ASM inspectionand graphed on the DTR. Because the ASM is a steady-state testmode (no accelerations or decelerations) you should not see anysignificant spikes in emissions levels at any point of the test.However, if the scale of the y axis (emission levels) is quite small(e.g. 0-50 ppm) you will see a lot more variation than you would ifthe scale was 0-500 ppm.

Variation in the HC and CO levels during the ASM test could be dueto an intermittent loss of fuel control. This is a fairly commondefect on vehicles with closed loop systems but even if the vehicledoes not have a closed loop system, it can still have erratic fuelcontrol problems.

If the emissions for the vehicle you are diagnosing are consistentlylow at idle and at 2500 rpm in neutral, but are somewhat higher onthe DTR graphs, that is a good indication of a weak catalyst. Thisis because the ASM is a higher exhaust flow condition than idle and2500 rpm.

If the general trend evident in the DTR is a gradual decline inemissions over more than 30 seconds, that is a pretty goodindication of a lazy catalyst. A good example of what this looks likeis Figure 8.

ASM DTR Examples

In Figure 8 and Figure 9 on the following pages, an ASM DTR froma vehicle with a lazy catalyst is shown along with an ASM DTR for avehicle that is running normally. There are a number of things totake note of in these DTRs:

• Refer to the scale shown at the left for the individual graph that you are looking at. The scale is different for every graph.

• The emission levels at the beginning of the test shown in Figure 8 are in the range that you would expect to see for engine-out concentrations. This indicates little or no catalyst activity. Continuing through the test, the downward trend in HC, CO, NOx, and O2 indicates that the catalyst is gradually becoming more effective. The clue that this is caused by a defective (lazy) catalyst is the time. Remember that a good catalyst should never take any longer than 60 seconds to reach maximum efficiency.

• The example shown in Figure 9 is from a 1988 vehicle with the original catalyst on it. This is a good example of a vehicle with normal degradation. It is certainly not as clean as it would have been when new, but it is nowhere near failing. The test duration is about 30 seconds because the vehicle fast-passed.

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Figure 8: ASM DTR Graphs Showing What Appears To Be A Lazy Catalyst

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Figure 9: ASM DTR For 1988 Vehicle Running Normally (Fast-Pass)

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D147 DTRs

Opacity is measured during D147 inspections of diesel-fueledvehicles. Opacity is a measure of how much light is absorbedtrying to pass through a plume of smoke. The thicker the smoke,the higher the opacity.

Typically, you will see spikes in the opacity readings at eachacceleration on the driving trace, most notably near the beginningof the test and also from the 60 second mark to the 90 secondmark. How high those opacity spikes are will depend on howclosely the vehicle’s fuel system is matching the fuel delivery withthe engine’s fuel requirements.

D147 DTR Examples

The example DTR shown below is from a 1995 Dodge Ram 3500that appears to be performing correctly. As with all DTRs, note thescale of the vertical axis.

Figure 10: D147 DTR For 1995 Vehicle Running Normally

The example DTRs shown on the next page are from a 1983 Toyotapickup before and after repairs were made. To correct theexcessive smoke, the injectors were overhauled and the injectionpump was adjusted to manufacturer’s specifications.

The opacity results for this vehicle were 90.61% before repair and14.91% after repair. At first glance at the before and after-repairDTRs it may not seem like much improvement has been made. Thisis because the y-axis (vertical) scale is not the same on Figure 11and Figure 12. To reinforce that point, have a look at Figure 13.

Figure 13 is from the same test as Figure 12 but the y-axis(vertical) scale has been changed to match that of the failedinspection DTR (Figure 11) in order to illustrate the effect of thevertical scale when looking at DTRs.

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Figure 11: D147 DTR Showing Extremely High Opacity

Figure 12: D147 DTR Showing After Repair Opacity

Figure 13: D147 DTR Showing After Repair Opacity - Same Scale As Fail DTR

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Chapter 6Obtaining Additional

Diagnostic Information

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Chapter 6 - Obtaining Addit ional Diagnostic Information

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Detailed Inspection DataA good diagnostic technician will review all of the availableinformation to develop a diagnostic strategy and then perform therequired component or system testing to pinpoint the root cause ofan emissions failure. To look at a vehicle's emission trends in moredetail, view a vehicle's OBD report, or determine the reason for anaborted inspection, you may wish to view the vehicle's detaileddata on RepairNet.

The detailed data available on RepairNetwill vary depending on thetype of inspection the vehicle received. For vehicles receiving atailpipe test, the Detailed Data or Second-By-Second report showsall of the measured emissions graphically on a single chart usingppm and % as the units of measure, with the addition of a texttable below it. In fact, for ASM, Idle and D147 inspections thisdata is identical to the data used to generate the DTR in theinspection centres - it is just displayed differently.

For IM240 inspections the SBS data is derived from a reversedilution correction formula and won't be absolutely accurate inevery case because of the variation in exhaust flow during atransient test. However, this is still extremely valuable todetermine emission trends in units that technicians arecomfortable with.

For an OBD inspection the Detailed Data will show the DiagnosticTrouble Codes (DTCs) recorded at the time of inspection as well asa description of the code for generic DTCs. No description isprovided for manufacturer specific DTCs. The readiness monitorstatus for each OBD inspection or attempted inspection is alsoindicated.

If an inspection is aborted, you can view the reason for theaborted inspection. In the case of an OBD inspection you caneasily see if the vehicle was presented for inspection in a Not -Ready condition, the vehicle will not communicate through theOBD connector etc. If the aborted inspection was a tailpipe test, adescription of the reason for the aborted test will also be provided.This will enable you to easily determine what action to take toensure a vehicle is in a testable condition when it returns for aninspection.

How To Obtain Detailed Data ReportsDetailed Data reports have been available on RepairNet forinspections performed since September 2000, and this feature wassignificantly enhanced in January 2007. You can access theDetailed Data report for a particular vehicle once you haveconnected to RepairNet and have entered the registration number

Detailed Inspection DataChapter 6 - Obtaining Addit ional Diagnostic Information

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for the vehicle you are interested in. You no longer are required tolog on to access this information.

On the Inspection Results screen each line represents an individualinspection. To the far right you will find an icon that indicates thetype of inspection the vehicle received. Click on the icon to openthe Detailed Data window for any given inspection. All of theDetailed Data available for that inspection is available with justone click of your mouse.

Figure 14: Detailed Data Links in Inspection History Section of RepairNet

For a complete description of the procedure for accessingRepairNet and obtaining the Detailed Data Reports refer to theAirCare RepairNet User Guide.

How To Read the Second By Second (SBS) ReportsDetailed Data reports for ASM. IM240, and D147 inspectionsinclude both graphical (see Figure 15 on page 61) and tabular (seeFigure 16 on page 61) Second By Second data on the same page.The table is shown below the graph so you may need to scrolldown the page to see it.

Each line of the table represents one second of the test. Thenumber of lines will vary depending on test duration:

• 22 seconds for idle tests

• 90 seconds for ASM tests

• 240 seconds for IM240 tests

• 147 seconds for D147 tests

NOTE: The above test durations are for inspections where the finalresult is fail. If you are viewing SBS data for a passed inspection,remember that the test duration could be much shorter because offast-pass algorithms that cut the test short if it can be determinedsooner that the vehicle is emitting normal levels.

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Figure 15: Second By Second Graph

Figure 16: Second By Second Table

NOTE: The SBS table in Figure 16 is abbreviated to fit on this pageand shows only the first 25 seconds of the test.

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The number in the first column of the SBS table (see Figure 16) isthe time (second) of the test. Looking across each line of the tableyou can see the vehicle speed and the individual emission readingsfor that second of the test. The emission readings are in parts permillion (ppm) or percent (%) as applicable.

The key to understanding the data is knowing what the vehicle isdoing (accelerating, decelerating, cruising, idling) at each point intime. The best indicator of what the vehicle is doing is the vehiclespeed, which is shown in the second column of the table. Byviewing the difference in vehicle speed from second to second youcan determine exactly when it is accelerating, decelerating,cruising, or idling. In addition, the rate of change in vehicle speedfrom second to second indicates how rapid the acceleration is. Thisis important when evaluating a CO spike because of the need forenrichment under hard accelerations.

For Idle inspections you will notice the vehicle speed column is notused and a Dilution Correction Factor column appears at the rightside of the table. This indicates a multiplier that is applied to theraw analyzer readings for each second of the Idle inspection. Thiscorrects for any exhaust dilution that may take place on vehiclesthat are equipped with an air pump or pulse air system. You mayhave observed this feature on some repair grade gas analyzersthat display "corrected CO" or a similar heading as part of itsreporting or display. Significant dilution can also occur if thevehicle has exhaust leaks or combustion problems.

IM240 SBS readings are derived from the actual measurementsduring the test using a "reverse dilution correction formula".Because of the widely varying dilution factor relative to changingexhaust flow conditions in a transient emissions test, thesereadings should be used with some caution. IM240 SBS readingswill not be as accurate as the grams per kilometre DTR for everyscenario, however as previously stated, viewing the convertedSecond-By-Second data is still extremely valuable.

How The SBS Readings Can Assist Your DiagnosisThe SBS data can be used in similar ways as the graphs on theDTR. Both display emission levels at each second of the inspectionso the data can be used to assist your diagnosis in the same ways.For some examples of what emissions trends to look for whenevaluating SBS reports, see “Using The DTR To Assist YourDiagnosis” on page 47.

For IM240 inspections, the SBS data may be even more helpful toyou because it shows emission levels in parts per million andpercent rather than in grams per kilometre. However, you must becautious because this data is derived from the actual dilutemeasurements and may not be entirely accurate. This is especiallytrue for the calculated oxygen concentrations.

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Previous Inspections and Repairs

How To Obtain Previous Inspection and Repair InformationOn RepairNet you can display the history of previous inspectionsfor individual vehicles. If you are certified, you can also view thehistory of all repair data entered for a particular vehicle.

Once you have connected to RepairNet and enter a vehicle'sregistration number, the Inspection History screen is displayed. Inthe bottom section, AirCare inspection data is shown with each linerepresenting an individual inspection. The inspections are listed indescending order with the most recent inspection on the first line.

To display a vehicle's Repair History, you must have valid log-incredentials (either a shop or a tech). Once you have successfullylogged in, select Repair History from the Repair Data drop-downnavigation menu at the top of the page.

For a more complete description of the procedure for accessingInspection History or Repair History on RepairNet, refer to theAirCare RepairNet User Guide.

How Historical Information Can Assist Your Diagnosis

Previous Inspection Results

Looking at previous inspection information can assist in severalways:

• the readings taken during previous inspections when the emissions defect didn't exist can give you and your customer a good sense of what the vehicle is capable of.

• in many cases, where you are dealing with a degraded catalyst for example, you can see a gradual deterioration over time by looking at the emissions performance for several years leading up to the present time.

Previous Repair Data

Looking at previous repair data can also be of assistance in certaincircumstances:

• when reviewed in conjunction with previous inspection results, you can observe the effect of specific repairs made in the past and the effects those repairs had on emissions.

• conversely, you can observe which repair actions had little or no impact on a vehicle's emission performance.

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• you can observe which recommended repairs were declined by the customer previously.

• you can easily identify vehicles which have been conditionally passed year after year because the motorist has not authorized the recommended repairs. In this scenario you may want to review the vehicle's repair history with the customer at the time the repair order is being written. You may be able to prevent a headache.

• when reviewing repair history, keep in mind that any outstanding defects are the results of another technician's diagnosis. There is no guarantee that a previous diagnosis was accurate or complete. Always perform your own thorough diagnosis!

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Chapter 7OBD Diagnostic Procedures

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Chapter 7 - OBD Diagnostic Procedures

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OverviewIn this chapter we provide recommendations for the diagnosis andre-inspection of On-Board Diagnostic (OBD) test failures.

Vehicle subject to OBD inspection at AirCare inspection centres are1998 & newer light-duty vehicles. All of these vehicles areequipped with OBD II systems but in this manual may be simplyreferred to as OBD.

Most 1998 & newer vehicles will receive an OBD test so long as theReadiness Criteria has been met with the following exceptions;

• all alternative-fueled vehicles will be given an IM240 test.

• all heavy-duty vehicles (GVW greater than 3855kgs / 8500 lbs) will be tested using the IM240 inspection procedure

• all vehicles will receive the same type of inspection on retest as they received on initial inspection.

Diagnosing OBD failures requires a different approach than tailpipeemissions test failures. In each case, you must refer to the vehiclemanufacturer’s recommended procedure for identifying the actualdefect that is identified by the OBD system.

Once the cause of the failure is identified and repaired, there aresome additional considerations related to preparing the vehicle forre-inspection that are unique to OBD failures.

OBD II Operational OverviewOBD II evolved from the California Air Resources Board's (ARB)desire to simplify and enhance their I/M program by requiringmanufacturers’ to improve their vehicles ability to monitor itsemission control systems.

OBD II standardized many aspects of monitoring, interrogatingand diagnosing a vehicle's OBD system:

• The Diagnostic Link Connector (DLC) is the same 16-pin configuration on all OBD compliant vehicles.

• Diagnostic Trouble Codes (DTCs) are standardized using 5 character alphanumeric indicators that provide specific information relating to the system, whether the code is generic or specific to the vehicle manufacturer, the affected sub-system and finally, a descriptor or indicator as to the nature of the failure.

• Vehicle manufacturers had to ensure their vehicles could communicate to a generic scan tool using one of the accepted communication protocols.

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All light-duty vehicles certified for sale in the US market were OBDII compliant by 1996. All light-duty vehicles sold in Canada had tobe OBD II compliant by the 1998 model year.

OBD II systems are designed to illuminate the vehicle'sMalfunction Indicator Lamp (MIL) if a defect is detected that couldcause emissions to rise to 1½ times the emissions certificationstandard.

Whenever a fault is detected, the MIL is illuminated and the OBDsystem may operate in a fail-safe strategy to limit the potentialenvironmental impact or to prevent damage of certaincomponents. For example, if a misfire is detected that is severeenough to damage the catalytic converter (commonly referred toas a Class A misfire), the MIL may flash to alert the motorist that avery serious malfunction is occurring. If the misfire continues, theMIL will eventually stay illuminated until corrective repairs arecompleted. While the MIL is flashing, the PCM may turn off theoffending cylinder(s) injector to protect the catalytic converterfrom thermal failure.

When the vehicle's PCM detects a problem it may or may not set aDTC on the initial trip the malfunction is detected, depending onthe nature of the defect. Defects considered to be one trip DTCsrequire immediate corrective action, therefore the MIL illuminatesstraight away. Two trip DTCs are set in a different manner. Whenthe PCM detects a problem, it will not illuminate the MIL rightaway. Instead the PCM will store a pending code in memory, andwait until a second occurrence before the MIL is commanded on.The next time the failure is detected, the pending DTC will nowmature to an actual DTC and the MIL will be turned on. The seconddetection of the fault generally needs to occur within 375 rpm andwithin 20% engine load of the first failure. This is important tokeep in mind. There is no point in clearing a two trip DTC andinforming the vehicle's owner that you would like to take a "waitand see" approach because this type of failure has alreadyoccurred twice, and the MIL will surely be on again in a very shortperiod of time.

If a vehicle completes three successful trips with no defect noted,the MIL will be commanded off by the PCM, however the code willbe retained in memory. Generally, the code will be automaticallyerased if that defect is not detected for another 40 warm-upcycles.

NOTE: Having codes retained in the PCM's memory will notgenerate an AirCare failure. The pass or fail outcome is determinedby the PCM's command of the MIL.

AirCare's policy on visual operation of the MIL is to note the MILstatus KOEO and KOER (key on engine running), however aproblem in this area will only be noted on the VIR as an advisorynotice to the motorist.

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Readiness Monitors

OBD II vehicles have an organized set of diagnostic routines totest specific components or systems that are referred to asReadiness Monitors. Once a Readiness Monitor has completed, thePCM will decide if any specific test has passed or failed. If amonitor test fails, a pending code will be set or, in the event it is aone trip code, a DTC will be set and the MIL commanded on.

Readiness Monitors can be divided into two groups, Continuousand Non-Continuous monitors.

Continuous Monitors

Most OBD vehicles have three Continuous Readiness Monitors:

• Comprehensive Component Monitor;

• Misfire Monitor; and

• Fuel System Monitor.

These monitors run continuously once the enable criteria havebeen met. Enable criteria are a set of conditions that need to bemet before a specific Readiness Monitor will begin to run. Thespecific details of the enable criteria will vary depending on thevehicle you are working on, so you must refer to your serviceinformation manual for details.

Once the enable criteria have been satisfied, the ContinuousMonitors will run continuously for the remainder of any trip. Inother words, you do not have to follow any specific drive cycle forthese three monitors to run. The Continuous Monitors will alwaysbe in a Ready status when viewed on a scan tool.

Non-Continous Monitors

Non-Continous monitors run only once per drive cycle or trip,provided the enable criteria have been met.

The following Non-Continuous Readiness Monitors may besupported on any given OBD II equipped vehicle:

• Catalyst Monitor

• Heated Catalyst Monitor

• Evaporative System Monitor

• Secondary AIR Monitor

• Oxygen Sensor Monitor

• Oxygen Sensor Heater Monitor

• EGR System Monitor

• PCV System Monitor

• Thermostat System Monitor

• A/C refrigerant System Monitor

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When viewing the Readiness Monitors on a scan tool you canobserve which monitors are supported, the monitors that are notsupported, and the status of each supported monitor. Theterminology used to indicate monitor status will vary depending onthe scan tool you use. You may encounter terms including Ready,Complete, or Done. All of these terms indicate that a monitor hasrun.

Re-Setting Readiness Monitors

Any time that you clear a DTC with your scan tool (or the battery isdisconnected) the Non-Continuous Readiness Monitor status will bereset to a Not Ready condition. To allow the Readiness Monitors tocomplete and be set to a Ready condition, the enable criteria mustbe met and a specific drive cycle followed. This information isavailable through the manufacturer's service information, as wellas several aftermarket publications. For more informationincluding some useful tips, see “Setting Readiness Monitors” onpage 78.

AirCare Readiness Policy

When OBD regulations were being drafted, regulators were wellaware that people can be very inventive to cheat a passing resulton their I/M test. One of the most common scenarios on pre-OBDII vehicles was to disable the MIL. This has been addressed byusing the PCM's command of the MIL to initiate an I/M failurerather than rely on the visual inspection of the MIL. Anothercommon occurence was to clear any DTCs, and immediately havethe vehicle inspected before the vehicle's self-diagnostic systemcould detect a fault. To deal with this scenario, regulatorsincorporated Readiness Monitor status into the OBD inspectioncriteria so that, if this method were attempted to get a vehiclethrough an I/M inspection, the vehicle would be deemed to be inan untestable condition and rejected.

All I/M programs allow some Readiness Monitors to be incompletein recognition of the difficulty some monitors are to complete dueto their design, ambient conditions, traffic patterns etc. For anAirCare Inspection the readiness criteria is slightly differentdepending on if the vehicle is in for an initial inspection or areinspection.

Initial OBD II Inspections

During an initial inspection, the lane software interrogates the PCMto determine the number of Readiness Monitors that are NotReady. If the number of monitors in a Not Ready state is 0 or 1,the software will proceed with the OBD inspection.

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If 2 to 3 Readiness Monitors are Not Ready, the vehicle will receivea fall-back IM240 inspection.

If 4 or more Readiness Monitors are Not Ready, the inspection willbe aborted. The vehicle will be rejected from testing, and themotorist informed that the vehicle cannot be tested until theReadiness Monitor criteria has been satisfied.

OBD II Reinspections

During a reinspection, if 0 or 1 Readiness Monitors are in a NotReady state, the vehicle is considered ready for an OBD inspectionand will pass so long as the MIL is commanded off.

If a vehicle's Readiness status indicates 2 or more ReadinessMonitors are Not Ready, the vehicle will receive a conditionalpass—if repair data has been entered in the system. If there is norepair data entered in the system, the inspection will be aborted,the vehicle will be rejected from testing, and the customerinformed that the vehicle cannot be tested until the ReadinessMonitor criteria has been satisfied.

NOTE: If the MIL is commanded ON, the Readiness Monitor criteriaare not used to determine if the vehicle is in a testable condition.The system has already determined the vehicle has a defectregardless of whether or not the appropriate number of ReadinessMonitors have completed.

Understanding OBD FailuresThe law states that a vehicle's OBD II system must illuminate theMIL if a condition is detected that could raise the vehicle’semissions to 1.5 times its certification standard. When this occurs,a DTC is stored in the PCM’s memory that relates to the defect.

That includes certain types of defects that you might notimmediately associate with emissions. For example, defectivetransmission components that can affect gear selection or torqueconverter operation may cause abnormal engine loads andtherefore fuel and spark calculations may in turn be incorrect,leading to increased emission rates.

This makes the pass/fail criteria of an OBD inspection quitesimple—if the MIL is commanded on, the vehicle fails. However,the criteria for determining a pass or fail result for an initial OBDinspection assumes two conditions:

1) normal communications are possible through the vehicle’s Data Link Connector; and

2) there is no more than one Readiness Monitor with a status of Not Ready.

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If either of these conditions are not met, the OBD inspection willnot proceed, and the vehicle will either be rejected or, dependingon the number of Readiness Monitors that are Not Ready, mayrevert to an IM240 inspection.

If a vehicle’s MIL is commanded on, the OBD system has detecteda condition that may result in emissions being 1.5 times theallowed maximum for that vehicle type. As a diagnostic technician,your job is to pinpoint the defect and repair it.

For more on the OBD inspection process, see the 2006-3 and2007-1 issues of the AirCare Repair newsletter.

The Diagnostic Process - OBD FailuresGenerally, the OBD diagnostic process will involve three stages:

1) gather information (inspection results, TSBs, DTCs and freeze-frame data);

2) follow the manfacturer’s flow charts to pinpoint the defect;

3) repair the defect and prepare the vehicle for re-inspection.

Once the defect is repaired, there are some special considerationsfor preparing the vehicle for re-inspection. See “Preparing theVehicle For Re-inspection” on page 78 for more details.

In some cases, a customer’s vehicle may have been rejected fromtesting due to an inoperative DLC or because there are two ormore monitors not ready. In these cases, which are not actuallyOBD failures, your diagnostic process will obviously be quitedifferent.

For more on inoperative DLCs and other communications problems,refer to “OBD Communication Problems” on page 77.

For more on Readiness Monitors, refer to “Setting ReadinessMonitors” on page 78.

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Gather Information

Review OBD Inspection ResultsOBD inspection results present a somewhat unusual scenariobecause, unlike tailpipe emission test results, there is not muchcommonality in diagnostic procedures among different vehicles. Ineach case, you must refer to the manufacturer’s recommendedprocedure for pinpointing the actual defect that is identified by theDTC.

OBD inspection results point to a specific circuit or system.However, they do not necessarily identify a faulty component. It isup to the diagnostic technician to pinpoint the fault by followingthe manufacturer’s recommended procedure.

Check For Any Related Service BulletinsVehicle manufacturers frequently issue software revisions thatchange how a vehicle functions. These can include driveability-related functionality and also OBD-related functionality. Suchrevisions are documented by the manufacturer in Technical ServiceBulletins (TSBs).

If a technician neglects to research these TSBs, it could result inmany hours of frustration and wasted diagnostic time. It would beunfair to bill a customer for hours of diagnostic time, when the realsolution could have been quickly identified in a Technical ServiceBulletin (TSB).

Record DTCs and Freeze Frame DataOnce you begin to perform an OBD diagnosis and repair, one of thefirst steps should be to print any DTCs and the stored FreezeFrame data. Alternatively, you could download an electronic recordfrom your scan tool to your PC. The logic of recording DTCs andFreeze Frame data at this stage is similar to baselining as youwould for a tailpipe emissions test failure.

When you erase the DTCs, you will also be erasing the FreezeFrame data and resetting the Non-Continuous Readiness Monitors.Always print or download a record of DTCs and Freeze Frame databefore erasing DTCs. This information will become very importantlater on in the diagnostic and repair process.

Additionally, an electronic record of the vehicle’s OBD status canbe very helpful in the future if another problem develops and theMIL illuminates again. If that were to happen, the customer isquite likely to suspect that the vehicle was not repaired correctlyin the first place. It would be much easier for you to explain toyour customer that a new problem has developed if you havesupporting documentation showing the OBD status then and now.

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DTCs

You may think that recording DTCs at this point in the diagnosticprocess is a redundant step, given this information is alreadyprinted on the AirCare inspection report. However, in some casesthe DTCs may have been erased and/or additional DTCs may bestored since the AirCare inspection.

Consider the following scenarios: perhaps it has been a while sincethe vehicle failed its’ AirCare inspection: perhaps someone hasattempted a repair or cleared codes since the vehicle failed its’AirCare inspection; or perhaps the fault that caused the originalDTC has not re-occurred since that time. In any case, it makesgood sense to establish the current status of the vehicle as a pointof reference.

Freeze Frame Records

OBD II regulations require that PCMs store several key pieces ofengine data at the time an OBD failure is detected. Generally thisFreeze Frame data will be retained in memory and will not beoverwritten unless a second, higher priority fault is detected.

If a second fault occurs that is higher priority than the first, theoriginal Freeze Frame data will be overwritten. Typically, a fuelsystem or misfire is considered to be a higher priority fault thanmost others. Most generic scan tools will indicate which DTC theFreeze Frame data is related to.

Freeze Frame data is useful for several purposes:

• determining the vehicle operating conditions at the time a particular defect occurred;

• verifying a repair; and

• aiding in preparing a vehicle for an OBD inspection.

These topics are covered in more detail later on in this chapter. Formore details on verifying a repair, see “Verify Your Repair” onpage 78. For more details on preparing a vehicle for re-inspection,see “Setting Readiness Monitors” on page 78.

Remember the Possibility of Hidden or Blocked DTCs

If a particular component or system has failed on an OBD IIequipped vehicle, the defect may have prevented one or moremonitors from running.

For example, if a vehicle’s downstream O2 sensor has failed, thecatalytic converter monitor will not have run since the PCM notedthe defect. If the catalyst was defective, the OBD system will nothave detected it yet. Once the O2 sensor defect is corrected, thecatalyst monitor will allow a pending code to set on the first trip.On the second trip, the pending code will mature and the MIL willagain be illuminated.

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It is important for a shop to educate their customers that someOBD II failures will stop some of the diagnostic tests from running.If the MIL has been illuminated for a significant period of time,critical diagnostic tests on other components or systems may havebeen suspended since the MIL was first illuminated.

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Pinpointing the Defect

General Guidelines For Diagnosing and Repairing OBD FailuresMost importantly, it is almost impossible to pinpoint OBD failureswithout the appropriate reference material. There is lots ofvariation from model to model in the specific components, signalsand calculations used to flag a defect and set a DTC. For thatreason, it is imperitive that you follow the manufacturer’srecommended procedure for diagnosing each and every OBDfailure. If you do not have the manufacturer’s recommendedprocedures at your disposal, get them.

As an example of why this is so critical, consider this scenario:

Let's say you are working on a vehicle that failed its’ AirCareinspection with a P0401 DTC (Insufficient EGR Flow). It would bequite logical to assume that this is likely caused by a restriction inthe EGR passage or by a faulty valve. You may be surprised toknow that this could be caused by a defective MAP sensor. Why?Under periods of deceleration, the MAP sensor is used by the PCMto determine whether proper EGR flow is delivered. An inaccurateMAP signal can lead the system to conclude that there isinadequate EGR flow. If the manufacturer’s recommendedprocedure were followed, this would be a fairly straightforwardrepair. However, if you fly by the seat of your pants using generictroubleshooting methods, it is very likely you would waste lots oftime.

Establishing Priorities on Failures With Multiple DTCsSometimes a single defect may cause multiple DTCs. If multipleDTCs are present in the vehicle you are diagnosing, you will needto establish priorities for troubleshooting—in other words, whichDTC flow chart to start with.

First, check the manufacturer’s recommended procedures for thatcombination of DTCs. There may be specific guidelines on whatDTC is the highest priority. If so, as always, follow themanufacturer’s recommended procedures.

Otherwise, here are a few general rules to keep in mind whendeciding which DTC to diagnose first.

1) Repair any DTCs associated with an internal PCM failure

2) Repair any DTCs indicating electrical or system voltages out of range

3) Repair any component DTCs

4) Repair any system DTCs

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OBD Communication ProblemsAs mentioned previously, all Canadian market light-duty vehicleswere required by law to be OBD II compliant from the 1998 modelyear onwards. This means that they MUST be able to communicatethrough the Data Link Connector (DLC). If a vehicle can'tcommunicate through the DLC the vehicle will be rejected frominspection until this is corrected.

If a vehicle has an engine change performed and as a consquenceis no longer able to communicate via the DLC, the vehicle will berejected from testing and required to be made OBD compliant. Formore information on engine swaps, see Appendix A - "EngineExchanges".

Some manufacturers use multiple diagnostic connectors includingthe required DLC along with their own proprietary connector in asecondary location. Even though a vehicle may communicatethrough the proprietary diagnostic connector and have noassociated DTCs, it will be rejected from the AirCare inspection if itcannot communicate through the DLC.

Similarly, some vehicles have multiple communication networksthat use the DLC. One communication network complies with theOBD II regulations, and a second communications network mayprovide additional diagnostic information through the same DLC.Again, the vehicle must be able to communicate to a generic scantool to be testable at an AirCare Inspection centre. If a vehiclecommunicates through a proprietary network but not the genericOBD II protocol, the vehicle will be rejected until this situation hasbeen corrected.

Vehicles can also develop wiring defects or module failures thatcan shut down a communication link. For example, OBD IIequipped Volkswagen and Audi vehicles are susceptible tocommunications problems cause by aftermarket stereos. This isdue to improper use of the factory wiring connector which, on1998 and newer Volkswagen and Audi vehicles, includes acommunications network circuit.

If a vehicle will not communicate, follow the vehiclemanufacturer's recommended procedures to pinpoint and repairthe defect. A good electrical diagram and component locator are amust for this type of repair. If the wiring tests OK, disconnect eachof the nodes or modules on the network one at a time, whilemonitoring scan communication as each module is disconnected. Ifcommunication is restored with disconnection of any node, thisindicates that component is disabling the network.

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Preparing the Vehicle For Re-inspection

Verify Your RepairOnce you have pinpointed and repaired the defect, you shouldverify your repair. For OBD-related repairs, vehicle manufacturersoften have specific verification procedures to ensure a vehicle hasbeen correctly repaired before returning a vehicle to its owner.Whenever available, these procedures should be adhered to.

If manufacturer’s repair verification procedures are not availablefor the specific vehicle you are repairing, follow this procedure:

• clear DTCs or complete three successful trips to turn the MIL off;

• ensure the system monitor for the DTC(s) that were set has completed and that there are no DTCs or pending codes stored in memory;

• if available, follow the manufacturer’s recommended drive cycle for the specific monitor you are concerned with. If not, drive the vehicle under the same operating conditions that existed when the Freeze Frame data was stored during the initial code setting

In every case, what you are trying to achieve is to give thevehicle’s OBD system an opportunity to run its monitors and toensure it does not identify any defects. For more details, refer tothe next section "Setting Readiness Monitors".

Setting Readiness MonitorsThe previous section described how best to ensure a vehicle hasbeen correctly repaired before returning it to its owner. Similarly,to ensure that a vehicle is ready for re-inspection, you mustensure that all Readiness Monitors have run.

If 2 or more Readiness Monitors are Not Ready, the re-inspectionresult will be a conditional pass. Your customer will not be happywith that result. Even worse, if you forgot to enter repair data forthis vehicle, it won’t even get a conditional pass—it will berejected from testing.

To avoid this situation, always follow the manufacturer’srecommended drive cycle to ensure the vehicle is operated in amanner that will allow the monitors to complete. Otherwise, followthese general guidelines to allow the Readiness Monitors tocomplete as quickly as possible:

Ensure all precondition and enable criteria have been met.

Check the appropriate repair information to determine the exactconditions required before a monitor will run. For example, if anEVAP or O2 sensor monitor's enable criteria indicate that a

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minimum six-hour cold soak is required, driving the correct drivecycle repeatedly will not allow the monitor to even begin to run letalone complete. A six-hour cold soak is required.

Ensure the vehicle has the correct fuel level.

OBD II EVAP monitor enabling criteria usually require that thevehicle's fuel level be between ¼ and ¾ full before the monitor willrun. In practice, ensuring that the fuel level is between ½ to ¾ fullallows the monitor to complete more quickly. Also, drive thevehicle in a smooth manner to eliminate fuel slosh.

Road test the vehicle on flat roads.

OBD monitors are designed to run during a vehicle's emissioncertification test (Federal Test Procedure or FTP), which isperformed at zero grade. Operating a vehicle on hills may preventthe monitor from completing because the reported engine load willnot be in an acceptable range. Also, accelerate and decelerate thevehicle as smoothly as possible.

NOTE: Readiness Monitor status is recorded as part of theinspection process. This data is available to you on RepairNet forcompleted inspections AND aborted inspections (unless the vehiclecould not be interrogated). Abort Code 22 indicates that theinspection was aborted because the required Readiness Monitorswere not set. In addition, you can also view the status of eachMonitor at the time of inspection. For more details on accessingdetailed inspection data on RepairNet, see the RepairNet UserGuide.

If You Have Trouble Getting All Monitors To RunVehicles that are free of defects will usually run their ReadinessMonitors fairly quickly. If you have followed the correct procedureto allow a monitor to run and it is not completing, check for TSBsrelated to this particular Readiness Monitor. There may be someother defect that is preventing the monitor from running—perhapsone that has not yet been detected by the OBD system.

Special Note Regarding 1998 Volvo OBD Monitors

Be aware that the precondition and enable criteria for 1998 VolvoOBD monitors to run may be unusually time consuming. For thatreason, these vehicles will not be rejected from re-inspection dueto monitors not being set. If you have repaired a 1998 Volvo, youshould make a reasonable attempt to get the OBD monitors to run,but at the very least, you must ensure your repair is successful byverifying normal operation under the same operating conditionsthat existed when the Freeze Frame data was stored during theinitial code setting.

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Other Alternatives You May Want To Consider

Don’t Clear the DTCs

Clearing DTCs also turns the MIL off and sets all the Non-Continuous Readiness Monitors to Not Ready. If you want to avoidhaving to complete drive cycles to allow the monitors to run, youmay want to consider the option of not clearing the DTCs. Thismethod ensures that the readiness monitors remain in a Ready orcompleted state, even though the DTC(s) may remain in memoryfor 40 warm-up cycles.

Of course, you still need to ensure that the MIL is commanded off.For most DTCs, the PCM will turn the MIL off by itself after threesuccessful trips are completed without a fault being detected.Some notable exceptions to this include catalyst and evap DTCs.For those defects, clearing DTCs and resetting is the best option.For other defects, the following procedure may be helpful.

To extinguish the MIL without resetting monitors:

1) view the Freeze Frame data to determine under what operating conditions the failure occurred;

2) road test the vehicle and operate it under similar conditions to those found in step 1; and

3) shut the engine off for several seconds and repeat the above road test two additional times.

At this point, the MIL should be turned off by the PCM.

Have the Customer Complete the Readiness Monitors

Sometimes an OBD system’s monitor enabling criteria and drivecycle routines make it difficult, time consuming, and not very costeffective for you to complete all of the readiness monitors. If so,another method is to return the vehicle to the motorist with clearinstructions that the vehicle must be driven for several days beforereturning to the inspection centre for re-inspection.

Make sure you instruct your customer to drive the vehicle as theynormally would for a week or so and then bring it back to yourshop so you can confirm that their vehicle is now ready forinspection. This also provides you the opportunity to ensure yourrepair was effective and that no hidden or blocked DTCs haveappeared as pending codes or matured DTCs.

The amount of time before your customer runs out of insurancewill be a factor in deciding if this method is practical or not. If youdecide to use this approach it is extremely important to clearlycommunicate this to your customer, and to document the aboveinstructions on the invoice or repair order.

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Make sure your customer understands that unless they bring thevehicle back for you to ensure the vehicle is ready for re-inspection, they run the risk that their vehicle may only receive aconditional pass, and they will be forced to return for anotherinspection next year.

Finally, make sure that you inform your customer of any specificoperating conditions that may be necessary for the monitors tocomplete. Generally, operation in a smooth manner will allowfaster monitor completion. Depending on the specific vehicle andmonitors, the following may also be required:

• an appropriate fuel level for EVAP Monitor completion

• operation at highway speeds to allow catalytic converter monitor completion

Remember, AirCare's reinspection policy is no more than 1readiness monitor can be incomplete.

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Chapter 8Diagnostic Procedures

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Chapter 8 - Diagnostic Procedures

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OverviewIn this chapter we provide recommendations for the diagnosis oftailpipe emissions test failures. Unfortunately, there isn’t a step-by-step procedure that will lead you to the correct diagnosticconclusion for every possible scenario.

Many factors come into play that affect what action you shouldtake to arrive at the correct diagnosis in the most efficient way.Each situation must be evaluated on an individual basisconsidering all of the available information.

That is not to say that it will always be a complex and difficult taskto identify the defect that caused a vehicle to fail its AirCareinspection. In fact, in many cases the cause of the problem can benarrowed down to only a few possibilities without even looking atthe vehicle. Just looking at the inspection results and otherinformation available to you can often eliminate many of thepossible causes of emissions failures. Some examples of this arediscussed in this chapter for each type of inspection.

Safety PrecautionsThe Workers’ Compensation Board (WCB) of BC establishesstandards and guidelines for occupational health and safety.Material published by the WCB should be consulted for a completelisting of precautions to ensure a safe workplace.

The precautions listed below do not take the place of anystandards, guidelines, or regulations established by the WCB. Theprecautions are included here simply as a reminder of the dangerstypically encountered when working on motor vehicles and theimportance of safe work practices for you and all of your co-workers.

• Always work in a well ventilated area and use efficient exhaust evacuation equipment.

• When working on or around fuel systems avoid using open flames, cigarettes, and electrical devices that could create a spark. Battery operated lights are safest.

• Relieve pressure before opening any fuel lines and always use proper caps for disconnected fuel lines.

• Always wipe up spills immediately.

• Keep a fire extinguisher handy.

• Always use wheel chocks.

• Use extreme caution when working underhood with the engine running, particularly in the vicinity of accessory drive belts.

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The Diagnostic ProcessGenerally, the diagnostic process will involve three stages:

1) reviewing the inspection results;

2) prioritizing the component tests that will lead you to the correct diagnostic conclusion in the most efficient manner possible; and

3) performing the component tests that are necessary to pinpoint the defect.

The first two stages of the process require that you consider theinspection procedure used (IM240, ASM, idle test, or D147), thepollutant and mode of failure, and the emissions control systemsused on the vehicle in question.

In the third stage (component testing), the procedures are thesame regardless of the type of emissions test used. You will testan O2 sensor the same way on a vehicle that failed an ASM test asyou would a vehicle that failed an IM240 test. However,manufacturer specific procedures and specifications should alwaysbe consulted to ensure accurate results.

BaseliningBaselining refers to the measurement and recording of a specificparameter prior to changing or adjusting something. A secondmeasurement can then be compared with the baselinemeasurement to determine the effect of the change.

Some technicians will instinctively see a need to do a baselineemissions test in the shop as a preliminary step in diagnosing anemissions failure. In some cases this is definitely worthwhile, butin other cases, it is just a waste of your time and your customer’smoney.

For example, if a vehicle has failed the ASM test for NOx, makingbaseline measurements of tailpipe levels for HC, CO, CO2 and O2at idle and 2500 rpm will not be of any value. However, baseliningengine-out CO, O2, and Lambda values would be a useful point ofreference that could be compared following repair actions such asdecarbonizing, injector cleaning, etc.

Continuing with this example, if you suspected a dirty MAF iscausing the excess NOx, it would also be worthwhile to baselinethe MAF by doing a road test and noting the indicated airflow priorto cleaning the hot wire. With a baseline established you canconclusively determine whether cleaning the sensor’s hot-wire hasresulted in any significant change or not. Any way that you caneliminate guesswork is beneficial to your diagnostic success.

Although making baseline measurements is often a wise diagnosticstrategy, how and what you should measure will depend on thespecifics of the situation. Measuring tailpipe emissions won’t be

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useful in many cases. The general guideline is if it is somethingthat you can reliably measure, then baselining is worthwhile. Withyour gas analyzer you can reliably measure HC, CO, CO2 and O2 atidle and high idle/no load conditions. If you are diagnosing anemissions defect that is evident under those conditions, thenbaselining the emissions is worthwhile. If the emissions problem isonly evident under load, in most cases a no-load emissionsbaseline isn’t going to be of much value.

Understanding Exhaust EmissionsAs an AirCare certified technician, you should be very familiar withperforming exhaust gas analysis. However, most of us need a bit ofa refresher from time to time. In Figure 17 and Figure 18 on thefollowing pages, some fundamental aspects of exhaust gasanalysis are provided for when you need a quick refresher.

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Figure 17: Exhaust Gas Analysis Tips

Gas Analysis In a Nutshell

Because exhaust emissions are influenced by so many things, acomplete explanation of exhaust gas analysis is beyond the scope ofthis manual. Below are just a few important tips to remember wheninterpreting emissions readings for fault diagnosis purposes.

• For vehicles that have exhaust after-treatment (catalytic converters and/or air injection) you must always consider engine-out concentrations and tailpipe levels for each emission. For example, if you measure .45% CO at the tailpipe, that could mean that fuel control is correct but the cat is dead, but, among other things, it could also mean that fuel mixture is as rich as 2.5% engine-out and the cat is working at about 80% efficiency.

• If emissions measurements are to be compared against each other (as in baseline testing) the vehicle operating conditions must be identical. Otherwise the comparison is invalid.

• You must always consider all emissions rather than just focus in on one of them.

• Engine-out NOx is related to combustion temperature and oxygen content.

• Engine-out CO is directly related to air/fuel mixture. A stoichiometric air/fuel ratio of 14.7:1 equates to about .45% CO.

• Lambda is the ratio of theoretical vs. actual fuel mixture. A vehicle operating at stoichiometric will have a Lambda value equal to 1.00

• Engine-out HC is related to everything. Valvetrain problems, compression problems, ignition problems, air/fuel ratio too rich or too lean, poor fuel distribution, and poor fuel atomization can all result in higher than normal HC.

• For vehicles equipped with catalytic converters, tailpipe emissions should be no more than 10% of the engine-out levels.

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Emissions vs. Air Fuel Ratio

Figure 18: Air Fuel Ratio Chart

10:1A/F Ratio

Average O2 Sensor Voltage

11:1 17:116:115:114:113:112:1 18:1

.74 .46 .42 .20

Stoi

chio

met

ric

HC

O2 CO

NO

x

Low

er E

mis

sion

s

CO2

CO2

CO2

CO2

CO2

NO

xNO

x

NOxNOx

CO

CO

CO

CO

CO

CO

HC

HC

HC

HC

HC

O2

O2

O2

Hig

her E

mis

sion

s

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Review Inspection Results

IM240 Results InterpretationHC, CO, and NOx are all measured in grams per kilometre (g/km)for IM240 inspections. While at first this may seem useless from adiagnostic point of view, it is perhaps even more valuable thanASM readings. IM240 readings are just a broader picture of avehicle’s overall emissions performance.

As with all types of emissions measurements, to interpret IM240readings you must relate the readings to what is normal. Whichemissions are abnormal, and by how much, can be clues as towhere the vehicle defect lies.

STEP 1: DETERMINE WHAT THE READINGS SHOULD BE

The inspection report shows the average passing readings forsimilar vehicles. This is a good indicator of what is normal.

Another indicator of normal emission levels may be the previousinspection results. However, be careful when comparing toprevious inspection readings; you will want to be sure that thevehicle did not also have a problem in the past even though it wasable to pass the inspection. For example, if a vehicle has adegraded catalytic converter it may have been deteriorating overseveral years. In this case, even if it passed, last year’s inspectionresults are not likely to be indicative of normal readings.

Also, when comparing to previous test results, be aware that fast-pass results are not directly comparable to full duration (240second) test results. For more information on fast-pass IM240tests, see the 2002-1 issue of the AirCare Repair newsletter.

In many cases, the additional detail provided by second-by-secondemissions data will be very useful when comparing fail results withpassing results. For more on second-by-second (SBS) data, seeChapters 4, 5, and 6.

STEP 2: IDENTIFY EACH EMISSION THAT IS HIGHER THAN

NORMAL

Even if only one emission exceeded the cutpoint, you mustcarefully consider all emission levels and identify any abnormality.This is critical to understanding what is going on with the vehicle’semission control systems.

STEP 3: NARROW THE RANGE OF POSSIBILITIES

If a vehicle has failed for CO but HC and NOx are very close tonormal levels, it is likely that the vehicle was running rich for asignificant portion of the inspection.

However, if a vehicle failed for CO but HC and NOx are both higherthan normal, another likely possibility is a dead catalyst. In anycase, you should now be able to list the possibilities and thecomponent tests that you will need to perform to pinpoint thecause of the problem. Then you can go on to prioritizing thosepossibilities and performing the necessary component tests.

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ASM Results InterpretationAs with all types of emissions measurements, to interpret ASMreadings you must relate the readings to what is normal. Whichemissions are abnormal, and by how much, can be clues as towhere the vehicle defect lies.

STEP 1: DETERMINE WHAT THE READINGS SHOULD BE

The inspection report shows the average passing readings forvehicles of the same type. This is a good indicator of what isnormal.

Another indicator of normal emission levels may be the previousinspection results. However, be careful when comparing toprevious inspection readings; you will want to be sure that thevehicle did not also have a problem in the past even though it wasable to pass the inspection. For example, if a vehicle has adegraded catalytic converter it may have been deteriorating overseveral years. In this case, even if it passed, last year’s inspectionresults are not likely to be indicative of normal readings.

STEP 2: IDENTIFY EACH EMISSION THAT IS HIGHER THAN

NORMAL

Even if only one emission exceeded the cutpoint, you mustcarefully consider all emission levels and identify any abnormality.This is critical to understanding what is going on with the vehicle’semission control systems.

STEP 3: NARROW THE RANGE OF POSSIBILITIES

If a vehicle has failed for CO but HC and NOx are very close tonormal levels, it is likely that the vehicle was running rich for asignificant portion of the inspection.

However, if a vehicle has failed for CO but HC is higher thannormal, and NOx is close to normal, it may be that the vehicle wasrunning rich for a significant portion of the inspection or that theoxidation capabilities of the catalytic converter are inadequate. Anadded consideration for vehicles that fail with very high CO is thatthe rich condition may cover up a NOx problem. For more on thissee “Are Other Problems Being Masked?” on page 96.

In a third scenario, if the vehicle failed for CO but HC and NOx areboth higher than normal, you are likely looking at a dead catalystor erratic fuel control.

In any case, you should now be able to list the possibilities anddiagnostic tests (component tests) that you will need to perform inorder to pinpoint the cause of the problem. Then you can go on toprioritizing those possibilities and performing the necessarycomponent tests.

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Idle Test InterpretationAs with all types of emissions measurements, to interpret idlereadings you must relate the readings to what is normal. Whichemissions are abnormal, and by how much, can be clues as towhere the vehicle defect lies.

STEP 1: DETERMINE WHAT THE READINGS SHOULD BE

The inspection report shows the average passing readings forvehicles of the same type. This is a good indicator of what isnormal.

Another indicator of normal emission levels may be the previousinspection results. However, be careful when comparing toprevious inspection readings; you will want to be sure that thevehicle did not also have a problem in the past even though it wasable to pass the inspection. For example, if a vehicle has adegraded catalytic converter it may have been deteriorating overseveral years. In this case, even if it passed, last year’s inspectionresults are not likely to be indicative of normal readings.

STEP 2: IDENTIFY EACH EMISSION THAT IS HIGHER THAN NORMAL

Even if only one emission exceeded the cutpoint, you mustcarefully consider all emission levels and identify any abnormality.This is critical to understanding what is going on with the vehicle’semission control systems.

STEP 3: NARROW THE RANGE OF POSSIBILITIES

Based on the first two steps, you now may be able to eliminate anumber of possibilities or you may even have a very good idea ofwhere the defect lies.

If a vehicle has failed for CO but HC is very close to normal levels,it is likely that the vehicle was running rich for a significant portionof the idle test. However, if a vehicle has failed for CO but HC ishigher than normal, it may be that the vehicle was runningextremely rich for a significant portion of the inspection or that thevehicle has more than one defect.

In any case, you should now be able to list the possibilities and thediagnostic tests (component tests) that you will need to perform inorder to pinpoint the cause of the problem.Then you can go on toprioritizing those possibilities and performing the component tests.

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D147 Results InterpretationThere are fewer variables to consider when diagnosing a dieselvehicle that has failed its AirCare inspection. As of this writing,opacity is the only AirCare standard that exists for diesel vehicles.That simplifies things considerably.

STEP 1: DETERMINE WHAT THE READINGS SHOULD BE

The inspection report shows the average passing readings forvehicles of the same type. This is a good indicator of what isnormal.

Another indicator of normal emission levels may be the previousinspection results. However, be careful when comparing toprevious inspection readings; you will want to be sure that thevehicle did not also have a problem in the past even though it wasable to pass the inspection.

STEP 2: NARROW THE RANGE OF POSSIBILITIES

Because we are only dealing with one emission (visible smoke) andit is directly related to fuel delivery, you may not be able toeliminate any possibilities at this stage.

Looking at the DTR, you may see that the opacity is highthroughout the test or only on the acceleration spikes. If opacity ishigher than normal throughout the test (even on mildaccelerations), this is indicative of a fuel injector problem. Ifopacity is only higher than normal on the major accelerations, it ismore likely that you have a rack adjustment problem. If adjustedto factory specs, the vehicle should easily pass.

In any case, you should now be able to list the possibilities and thediagnostic tests (component tests) that you will need to perform inorder to pinpoint the cause of the problem. Then you can go on toprioritizing those possibilities and performing the component tests.

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Prioritizing Component TestsAfter evaluating the inspection results and comparing the readingsto what they should be, you may have been able to narrow thefocus of your diagnosis. At this stage you will usually still have anumber of components or systems in mind that could be causingthe high emissions. But what should you check first?

Before jumping in and testing every component you see when youlift the hood, you should establish priorities for performing thespecific component tests that will lead you to pinpointing thedefect the quickest way possible.

Establishing PrioritiesThe highest priority should be given to the area or emissionssystem or component that seems to be the most likely cause of theproblem. However, you should also factor in how easy or difficultor time consuming it will be to conclusively check that componentor system.

For example, you may have a NOx failure narrowed down to eitheran EGR control system problem or a buildup of combustionchamber deposits. Even if you think it is less likely that the EGRsystem is at fault, it is a lot easier to check the EGR system thanto perform an overnight soak with a combustion chamber cleaningchemical.

FIRST PRIORITY IS ALWAYS FUEL CONTROL

Considering how important it is to emissions control and howcommonly it fails, the O2 sensor is certainly the highest priorityitem in virtually all circumstances.

Statistics show that the O2 sensor is by far the most commonlydefective component on failing vehicles. It is also the mostcommonly overlooked component. Most of the “Q” waivers (mis-diagnosed vehicles) evaluated in the AirCare Research Centre arefound to have O2 sensor related defects.

In every AirCare failure where the vehicle is equipped with one ormore O2 sensors, checking and ensuring that you have proper fuelcontrol under normal operating conditions (including driving)should be given the highest priority in your diagnostic sequence.

Even in older technology (carburetted) vehicles, correct fuelcontrol is of paramount importance. CO problems, HC problems,and NOx problems can all be caused by an incorrect air-fuel ratio.

If you have excessive HC and excessive CO, correct the richcondition first and then re-check for excessive HC, you may havekilled two birds with one stone.

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SECOND HIGHEST PRIORITY WILL USUALLY BE THE

CATALYST

It goes without saying that if the vehicle you are diagnosing wasnot manufactured with a catalytic converter, that this would not beapplicable to your diagnosis. Similarly, if you are dealing with aNOx failure on a vehicle equipped with an oxidation catalyst only,the cat would not be applicable to your diagnosis.

However, if you are diagnosing a vehicle with high CO and/or HCand the vehicle has a catalytic converter of any type, or if you arediagnosing a vehicle with high NOx and the vehicle has a three-way catalytic converter, checking the catalyst efficiency and feed-gas should be a high priority in your diagnostic sequence.

We know that for a three-way catalytic converter to workeffectively for all three harmful emissions, the correct balance offeed gas must be maintained. This is why you must ensure thatyou have proper fuel control first. If you do have proper fuelcontrol, the next most likely cause of the problem will usually bethe catalytic converter.

UNLESS THE VEHICLE IS NOT EQUIPPED WITH THOSE

SYSTEMS

Virtually all 1988 and newer vehicles were factory equipped withfeedback fuel control systems and a three-way catalyst. Those twosystems should certainly be given highest priority in yourdiagnostic sequence. However, there are several other possiblecauses of high emissions on such vehicles.

Figure 19: Emission Diagnosis Priorities

As shown in Figure 19, the highest priority items when performingan emissions diagnosis are: visual inspection, fuel control, andcatalyst efficiency. Obviously there are many other possible causesof excess emissions, however, these high priority (and highprobability) items should always be checked first.

Visual

Inspection

OK?

Check feedgas

and catalyst

efficiency for

HC & CO

Correct

problem

Correct fuel

control

problem

Fuel

Control

OK?

Is vehicle

1988 or

newer?

Check feedgas

and catalyst

efficiency

Is vehicle

equipped

with cat?

Move on to

other

component

checks

Did

vehicle fail

for NOx?

Is cat

three-

way?

Move on to

other

component

checks

Check feedgas

and catalyst

efficiency

Flowchart of Highest Priority Items When Diagnosing Emissions Defects

NO NO NO

NO NO NO

YESYESYES

YESYESYES

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Are Other Problems Being Masked?An added consideration if the vehicle you are diagnosing failedwith very high CO is the possibility that it may also have a NOxproblem that was masked by the high CO. Sometimes restoring theair/fuel ratio to the proper range uncovers a NOx problem. TheNOx defect may have existed previously but wasn’t evidentbecause of the lack of oxygen that accompanies a rich mixture.

If possible, you should perform a quick check of NOx controlsystems after identifying the cause of the CO problem. Anyproblems found should be included in the total repair estimate.However, in these circumstances any NOx related repairs would bea lower priority than the CO related repairs.

You should also explain to your customer that a NOx problem maybecome evident after the CO problem is repaired.

Possible Causes of High HCFor HC problems, the following systems (if applicable) will need tobe checked, usually in the order shown below:

1 ) lean or rich air-fuel ratio

If the fuel system is delivering a leaner than ideal air-fuel ratio,it may result in lean misfire and cause high hydrocarbons.Ensure that the air-fuel ratio is not lean under the operatingcondition(s) when HC is high.

If the fuel system is too rich, it also may result in high HC butwill be accompanied by VERY high CO as well.

2) vacuum leaks

There are many things that can cause disruption in the air andfuel getting to the cylinders and result in high hydrocarbons.Incorrect PCV valve/orifice flow rate can also cause similarsymptoms as a vacuum leak. EGR systems can also be thesource of HC problems. EGR valves often get stuck open at idleand faulty pressure transducers can cause excessive EGR flow.Both problems may cause excessive HC emissions.

For more information on the procedures for ensuring there areno vacuum leaks or other defects disrupting the air fuel mixturegetting to all cylinders, refer to “Performing Component Tests”in the next section of this chapter.

3) poor ignition performance

Ignition defects including fouled plugs, leaking or open hightension wires, or excessive secondary resistance all result in ashortage of spark energy. Any shortage of spark energy(voltage or duration) may result in incomplete combustion andcause high hydrocarbons. Use your oscilloscope or ignition

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analyzer to ensure that there is adequate spark voltage andduration for all cylinders under the operating condition(s) whenHC is high.

4) excessive spark advance

If the spark occurs too far before TDC, high hydrocarbons mayresult. Too much spark advance could be due to an incorrectadjustment or a defect in mechanical or vacuum advancemechanisms.

5) uneven cylinder balance

At this point you should be sure that the air-fuel ratio iscorrect, there are no external vacuum leaks, and the ignitionsystem is operating normally. There are still many possiblecauses of high hydrocarbons, most of which are internal engineproblems or tough to detect induction system problems such asvalve deposits, a leaking EGR valve, or some other leakingcomponent that is connected to manifold vacuum but wasn’tdetected earlier. Checking for uneven power output amongstcylinders will usually help to track down the cause of theproblem.

On fuel injected vehicles, poor fuel atomization is a commoncause of HC problems. Depending on accessibility, an injectorpower balance test may help to isolate injectors that areplugged or have a poor spray pattern. For more information onthese procedures, refer to “Performing Component Tests” in thenext section of this chapter.

Other Sources of HC Besides the Tailpipe

The exhaust emissions sample system used in IM240 tests draws alarge volume of ambient air along with the exhaust sample. That isan important thing to remember because it means that fuel vapourleaks can cause an HC failure.

For more information and examples of these types of defects, seethe 2002 #2 issue of the AirCare Repair newsletter.

HC Problems and Alternative Fuels

There are some unique issues that you should keep in mind whendiagnosing HC failures on propane and CNG powered vehicles.Because these are gaseous / low carbon fuels they require highervoltage levels to bridge the spark plug gaps. Therefore, thecondition of the ignition secondary circuit becomes even morecritical than other vehicles.

Another factor to be aware of is that these fuels are less reactive,requiring the catalytic converter to be of very good quality and ingood condition to maintain proper HC oxidation efficiency.

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Valve seat recession can also be a problem with vehicles operatingon alternative fuels. The first sign of this is high HC levels whenreturning to idle from high idle or driving. This will usually improvegreatly after one to two minutes at idle, as the hydraulic liftersbleed down.

Possible Causes of High COAs you know, high CO means too much fuel. Fuel can only comefrom three sources, the crankcase vapor control system, theevaporative control system, or the actual fuel delivery system. Thefuel delivery system is certainly the most likely culprit but in mostcases it is very quick and easy to eliminate the other twopossibilities first. However, if it is problematic to check theevaporative system purging, it is probably wise to go straight tofuel system diagnosis.

For CO problems, the following systems and possible defects willneed to be checked, usually (but not always) in this order:

1 ) excessive crankcase blowby or PCV flow

Excessive crankcase vapor flow or contaminated oil can bothresult in excessive CO emissions. Assuming the engine oil is notcontaminated and the PCV valve orifice is correct for theapplication, excessive crankcase vapors can only be caused byserious internal engine defects.

2) saturated evaporative control system

The charcoal canister should be purged at the correct time (seemanufacturer’s specifications) and should never result inexcessive CO for more than a few seconds.

When working correctly, a balance is maintained between thefuel vapors being drawn into the engine through the canisterpurge system and the fuel delivered through the carburettor orfuel injector(s). If a charcoal canister is saturated, this balanceis no longer maintained and excessive CO results.

3) rich air-fuel mixture

There are many aspects of the fuel delivery system that mayneed to be checked when diagnosing a rich air/fuel mixture.That is the main reason that this is listed behind crankcase andcanister systems—they are much easier and quicker to check.

When diagnosing a fuel delivery system, it is very important toconsider the operating conditions under which the vehicle is (orwas) running rich. This can help to narrow down thepossibilities. Is the rich condition intermittent or does it onlyoccur under certain loads?

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A good example of how you can narrow down the possibilities isif you are diagnosing a carburetted vehicle that failed an ASMtest for CO, but appears normal at idle and 2500 rpm. In thiscase you must consider load-sensitive possibilities like thepower valve and its control circuit or mechanism. However, it islogical to conclude that these symptoms cannot be caused byworn metering needles or jets because that would cause themain circuit to be rich all of the time.

Conversely , if you are diagnosing a vehicle that has failed forCO and is rich both at load and at 2500 rpm you know thatcannot be the result of a power valve opening prematurely.However, it may indicate a power valve or float problem that ispast the point of being load dependent (e.g. power valve stuckopen all the time).

In every case, list the possible causes of a rich mixture underthe conditions that the CO is high and eliminate those that arenot applicable. What you are left with are the things you mustsystematically check to pinpoint the problem.

Remember to consider the mechanical defects that may resultin the fuel system delivering more fuel than the engine actuallyneeds. For example, retarded timing will cause a higher thannormal throttle opening for a given load. Another example iscam timing that is one tooth out—this can make a significantdifference in the load (and therefore the fuel required) that isindicated to the PCM by the MAP sensor .

Possible Causes of High NOxFor NOx problems, the following systems (if applicable) andpossible defects will need to be checked, usually in this order:

1 ) over-advanced ignition timing

Initial advance, centrifugal advance, and vacuum advanceshould all be checked. Any of these could cause excessive NOx.

2) inadequate EGR flow

EGR operation should be checked completely. To do this thereare three areas that you must check:

• the EGR valve

• the EGR exhaust passage(s)

• the EGR control system

For more information on these procedures, see page 128.

3) lean air-fuel ratio

Check to ensure that there is not an excessively lean mixturebeing burned. Depending on the vehicle, its fuel system, and its

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emissions control systems, this may involve simply looking atthe VIR, measuring engine-out CO, CO2, O2, and lambdavalues, and O2 sensor testing. For more information on theseprocedures, refer to “Performing Component Tests” onpage 103.

4) feed-gas problem

High O2 levels upstream of a TWC can cause a reductioncatalyst to be ineffective at lowering NOx. Possible causes ofhigh O2 levels ahead of the catalyst that need to be checkedinclude a lean air-fuel ratio, an exhaust leak, and defects in theair injection system.

5) defective three-way catalytic converter

Studies have shown that if a catalytic converter has lost itsability to reduce NOx it also will be inefficient at oxidizing HCand CO. Test the catalyst by performing a converter efficiencytest (see “Catalytic Converter Testing” on page 108).

6) combustion chamber deposits

If the above possibilities have been conclusively checked and noproblems found, it is reasonable to conclude that combustionchamber deposits are contributing to excessive NOx emissions.Many techs have had good success with combustion chambercleaning chemicals if applied correctly. Generally, you shouldapply 500 ml (some manufacturers recommend more) of thecleaner through a large vacuum hose, stalling the engine afterall of the cleaner is induced into the engine. It is critical thatyou leave it soak overnight before restarting the engine.

Possible Causes of High Diesel OpacityFor diesel opacity problems (excessive smoke), the followingsystems (if applicable) and possible defects will need to bechecked, usually in this order:

1 ) restricted airflow

Any restriction to the flow of air into the engine can causeexcessive smoke emissions. This includes the air filter and theair inlet ducts from the air filter right on through to the intakemanifold. A restricted exhaust system may also cause areduction in the airflow into an engine under certaincircumstances.

2) injection timing

Make sure that the injection pump is timed to the correctcylinder and that timing is set to specifications. Refer to the

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manufacturer’s recommended procedure and specifications toensure that injection timing isn’t causing excessive smoke.

3) turbo pressure

Similar to the air filter and inlet ducts, the turbo pressure canaffect the smoke emissions of a diesel engine. You need toensure that the turbo is running at the correct speed andpressure. Use the manufacturer’s recommended procedure andspecifications to test for bad bearings and incorrect pressurecontrol.

4) injection quality

Nozzle or injection orifices that are restricted can causeexcessive smoke. Other injector defects such as worn valveseat, sticking nozzle, and incorrect opening pressure may alsocause excessive smoke. To test or clean injectors, they willneed to be removed and bench tested according to themanufacturer’s recommended procedures and specifications.

5) electronic fuel control devices

Exhaust Gas Recirculation (EGR) devices are used to controlNOx emissions in many diesel vehicles but if the rate of EGRflow is excessive, smoke emissions can increase significantly.

Most of the typical PCM inputs may be found on electronicallycontrolled diesel engines along with some additional and uniquedevices such as fuel temperature sensors, injection quantityfeedback sensors, injector position sensors, and catalystheating injectors. Refer to the manufacturer’s recommendedprocedures and specifications for testing of these components.

6) oxidation catalyst

Because of the excess air requirements of diesel engines, onlyoxidation catalysts are used. The performance of thesecatalysts can have a significant effect on smoke emissions.Refer to the manufacturer’s recommended procedures andspecifications for testing of these components.

7) compression

Engine integrity should be checked with a compression test asper manufacturer’s recommended procedure. Compressionpressures should be within 10% of each other.

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8) injection pump calibration

If all else fails, the injection pump may require an overhaul orcalibration check. Refer to the manufacturer’s recommendedprocedures and specifications for testing of these components.

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Performing Component TestsThis section provides general information on the testing ofindividual components that may cause excess emissions. Becausethere can be many variations in components from vehicle tovehicle, you should refer to the manufacturer’s recommendedprocedures and specifications when performing tests.

O2 Sensor TestingYou should be in the habit of checking O2 sensor performance onevery vehicle you work on because of the importance of O2sensors to controlling emissions, and the fact that it is verycommon for O2 sensors to wear out and fail.

To accurately evaluate the performance of an O2 sensor, you mustdetermine the voltage range, response time and number of crosscounts. To do this you will need to perform at least two tests: asnap-throttle test, and a cross-count test. Both use a digitalstorage oscilloscope (DSO) to monitor voltage over time.

Snap-Throttle Test

This test provides you with measurements for four importantparameters respecting O2 sensor performance:

• maximum voltage

• minimum voltage

• response time from rich to lean

• response time from lean to rich

The test quickly forces the fuel system rich and lean whilerecording the O2 sensor voltage. Because the DSO stores themeasurements, you don’t have to perform four tests to examinefour parameters. You perform the test and then observe fourdifferent aspects of the waveform.

Table 3: O2 Sensor Performance Criteria

Test Specification

Maximum voltage when forced rich greater than 900 millivolts (mV)

Minimum voltage when forced lean less than 100 mV

Maximum response time from lean to rich

less than 100 msbetween 300 mV and 600 mV

Maximum response time from rich to lean

less than 100 msbetween 600 mV and 300 mV

Cross counts at 2500 rpm at least 5 cross counts in a10 second period

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The O2 sensor response time is the amount of time that it takesfor the voltage to rise from 300 millivolts (mV) to over 600 mV, orto drop from 600 mV to less than 300 mV. Response must bechecked in both directions to conclusively check an O2 sensor.

Performing The Snap Throttle Test

1) Locate the O2 sensor signal wire and connect the signal probe of your DSO.

2) Connect the COM probe to the O2 sensor ground circuit or to the engine block.

3) Start the engine and run at 2500 rpm for a couple minutes while you adjust the DSO settings (see “DSO Setup For Measuring O2 Sensor Range and Response” on page 105). The DSO voltage scale should be 200 mV per division and the time scale should be 500 ms per division. Set the acquisition and trigger mode to automatic/normal.

4) Quickly snap the throttle several times and press the button on your DSO that freezes the waveform. Observe the waveform as outlined below.

Reading Maximum O2S Voltage

Looking at the waveform on your DSO, you should see a voltagespike (an increase and an accompanying decrease) for each timeyou snapped the throttle. Identify and record the highest voltageproduced by the O2 sensor. A good O2 sensor will generate morethan 900 mV under such conditions.

Reading Minimum O2S Voltage

Looking at the waveform on your DSO, you should see a voltagedip immediately following each snapped of the throttle. Identifyand record the lowest voltage produced by the O2 sensor. A goodO2 sensor will generate less than 100 mV under such conditions.

Measuring O2S response time

1) Note the 300 mV and 600 mV points on either an upslope or a downslope of the O2 sensor waveform. If your DSO has mea-surement cursors, set them at these points (see Figure 20 on page 105). The distance from left to right between the two cur-sors is the response time (see Figure 21 on page 105).

2) Measure this distance as precisely as possible using the cursor read-out or zoom feature. Record this value (in milliseconds).

3) Repeat steps one and two for the other slope (up or down). It is important to measure the O2 sensor’s response time from 300mV to 600 mV and from 600mV to 300mV.

You should see a response time of no more than 100 millisecondson a good O2 sensor. If not, perform the “More Conclusive O2Sensor Response Time Test” on page 106 to verify response timebefore condemning the sensor.

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Figure 20: DSO Setup For Measuring O2 Sensor Range and Response

Figure 21: Reading Response Time On DSO

The firstcursor isplaced at600 mV.

The secondcursor isplaced at300 mV.

DSO is set so that 0 volts is here

At 200 mV per division,1 volt is here

y ax

is =

vol

tage

(200

mV

per d

ivis

ion)

x axis = time (100 ms per division)

y ax

is =

vol

tage

(200

mV

per d

ivis

ion)

x axis = time (100 ms per division)

dX: 28.5714 mS dY: 329.714 mV

X1: 182.143 mS Y1: 629.143 mV

X2: 210.714 mS Y2: 299.429 mV

dX = the distancebetween the

cursors along theX axis. In this

case 28.5714 mS.

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More Conclusive O2 Sensor Response Time Test

In most cases it won’t be necessary to do an additional test tomeasure the O2 sensor response time. You can measure it usingthe waveform captured in the snap throttle test. However, if itappears that response time is not fast enough, perform thefollowing test to verify that the O2 sensor is defective beforecondemning it.

Performing the Response Time Test

1) Locate the O2 sensor signal wire and connect the signal probe of your DSO.

2) Connect the COM probe to the O2 sensor ground circuit or to the engine block.

3) Locate a large manifold vacuum inlet and attach a propane enrichment device.

4) Start the engine and run at 2500 rpm for a couple minutes while you adjust the DSO settings. The DSO voltage scale should be 200 mV per division and the time scale should be 500 ms per division. Set the acquisition and trigger mode to automatic/nor-mal.

5) Let the engine idle. You must perform the next step within 30 seconds.

6) Slowly and steadily apply propane enrichment. The system should compensate for the added propane by reducing the injec-tor pulse width (or leaning the mixture control solenoid duty if carburetted). Continue to apply more and more propane enrich-ment. Eventually (after about 20 seconds of adding propane) the system will usually run out of range to compensate for the added propane. Continue to add more propane and the engine will start to run rough and rpm may drop. Do not stall the engine.

7) Now that the engine is running extremely rich, quickly pull the propane source hose off of the vacuum inlet to instantly create a very lean mixture.

8) O2 sensor voltage should drop very rapidly (how rapidly is what you want to measure). After the drop in O2 sensor voltage has moved to the center of your DSO screen, press the button that freezes the waveform.

9) Measure the time that it took for O2 sensor voltage to drop from 600mV to 300mV (see Figure 21 on page 105). A good O2 sen-sor will take no more than 100 milliseconds.

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Cross Counts

Measurement of cross counts should only be made after 30seconds with a warmed-up engine operating at 2500 rpm. Thisshould be adequate time for a normally functioning O2 sensor tobe fully functional.

Performing the Cross Count Test

While maintaining a 2500 rpm high idle, record the number oftimes in a 10 second period that the O2 sensor voltage crosses themid-point of its range (450 millivolts). See Figure 22 on page 107.

Figure 22: O2 Sensor Cross Counts on DSO

Each upslope and downslope that crosses the mid-point should becounted as one cross count. A minimum of 5 cross counts shouldbe evident in a 10 second period. This minimum applies to oldersystems using throttle body injection or feedback carbs. Othersystems may have different minimum cross counts so you shouldconsult the manufacturer’s specifications.

Zirconia vs. Titania O2 Sensors

O2 sensors made with a zirconia ceramic are by far the mostcommon type. They generate a high voltage (1 volt) when theexhaust is rich and a low voltage (0 volts) when the exhaust islean. Zirconia O2 sensors may have one, two, three, or four wires,depending on whether a redundant ground circuit and/or a heateris used.

y ax

is =

vol

tage

(200

mV

per d

ivis

ion)

x axis = time (100 ms per division)

DSO is set so that0 volts is here

At 100 mV per division,1 volt is here

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O2 sensors made with a titania ceramic can be found on somevehicles manufactured by Chrysler/Jeep, Nissan, Toyota, andLandrover. Titania O2 sensors are unique in operating principlebecause, unlike the zirconia oxygen sensors, the titania sensorsare a variable resistor that works on a reference voltage and pullsit down to ground. The reference voltage is usually 1 volt but onsome vehicles, the reference voltage is 5 volts (see note below).

Testing of titania O2 sensors (range, response time, and crosscounts) is usually the same as for zirconia sensors. Thespecifications will usually be similar with the exception of voltagerange. For more information consult the manufacturer’sspecifications.

NOTE: Titania sensors in some vehicles (pre-1991 Jeep 4.0L forexample) use a 5-volt reference voltage and operate inversely tonormal. With these sensors, rich exhaust results in a low O2sensor voltage.

Catalytic Converter TestingTechnicians and equipment manufacturers have tried and tried tofind a conclusive yet non-intrusive way of testing the performanceof a catalytic converter. A visual inspection is only useful indetecting physical damage to the catalytic converter. Temperaturemeasurement may be useful in determining whether the cat iscompletely dead, but you cannot accurately determine thedifference between 60% and 80% catalyst efficiency by measuringtemperature. In other words, it is inconclusive.

There is only one way to conclusively check the performance of acatalytic converter—comparing gases sampled before and after theconverter.

For marginal IM240 failures you should evaluate catalyticconverter performance based on before and after testing inconjunction with a review of the DTR and SBS report (see “UsingThe DTR To Assist Your Diagnosis” on page 47 and “How The SBSReadings Can Assist Your Diagnosis” on page 62). Remember thatthe IM240 inspection procedure gives vehicles ample opportunityto pass and a borderline fail is still a fail.

Before and After Sampling

The concept of catalyst performance testing is pretty simple whenyou think about what the converter’s job is—to reduce the harmfulpollutants coming out the tailpipe. Determining how much they arereduced will give you a valid measurement of performance or, inthis case, efficiency.

The arithmetic is pretty basic. The difference between engine-outemissions (gases going into the catalyst) and tailpipe emissions

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(gases coming out of the catalyst) will give you the amount ofreduction. Dividing that amount by the amount that the catalysthas to deal with (engine-out emissions) will give you the reductionin a percent of total. This is the efficiency of the catalyst.

The formulae shown in Figure 23 can be applied to HC, CO or NOx:

Figure 23: Catalytic Conversion Efficiency Formulae

An example of the use of these formulae to calculate catalystefficiency is shown below in Figure 24.

Figure 24: Determining Catalyst Efficiency

RepairNet includes an efficiency calculator under the Resourcesheading on the main menu bar. You just enter the before and afterreadings and the calculator will give you the efficiency.

GAS IN - GAS OUT = AMOUNT OF REDUCTION

(AMOUNT OF REDUCTION ÷ GAS IN) = EFFICIENCY

EFFICIENCY x 100 = EFFICIENCY IN PERCENT

HC175 ppm

HC15 ppm

Exhaust Gas IN Exhaust Gas OUT

175- 15

= 160

160 175

= .91

.91x 100

= 91%

Step 1:

Step 2:

Step 3:

CatalyticConverter

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Guidelines For Acceptable Catalyst Efficiency

For vehicles tested using the ASM test procedure, the catalystshould be at least 80% efficient for HC and CO.

For vehicles tested using the IM240 test procedure, catalystefficiency will need to be 90% efficient or better for HC and CO.

Tips for Upstream Sampling

• The exhaust system must be free of leaks. Remember that due to positive and negative exhaust pressure pulsations, a leak will result in dilution of the exhaust. This can have a dramatic effect on your readings. Remember, you are trying to measure undiluted engine-out concentrations.

• The connection of your analyzer to the exhaust system should also be free of leaks. The best way to achieve this is to drill an 11/32” hole in the exhaust pipe and tap it to a 1/8” pipe thread. Connect your sample hose to a coiled length of brake line threaded into the pipe using a 1/8” NPT X 1/4” inverted flare connector. The coiled brake line allows the exhaust to cool before going into the sample hose. For more details see the 1997 #3 issue of the AirCare Repair newsletter.

• If your HC readings are higher at the tailpipe than what they are when sampled upstream, you may have excessive water in the muffler. With heat, HC in the water will evaporate and be detected by your analyzer. To resolve this, make sure the muffler drain hole is clear. You may need to high-idle the car or perhaps take it for a road test to get rid of the excess water.

• If you have access to a smoke machine, this is the ideal time and location to check for exhaust leaks ahead of the catalyst.

• When finished sampling upstream, seal the hole by installing a 1/8” NPT brass plug with anti-seize compound on the threads.

Other Methods of Catalyst Testing

In some cases, before-and-after sampling may not be a conclusivetest of a catalytic converter’s efficiency under certain operatingconditions. For example, let’s say you have sampled exhaust gasesupstream but you have found the feed-gas is good and the catalystefficiency is good when tested in the shop, yet the second-by-second readings suggest a weak catalyst. In such cases, it wouldbe wise to test catalytic converter efficiency while driving.

There may also be cases where upstream sampling isn’t practicaldue to catalytic converters being close-coupled to the exhaustmanifold. In either of these situations, an alternative method oftesting catalyst efficiency may be needed.

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Using OBD-II Catalyst Monitors to Diagnose Catalysts

If the vehicle is OBD-II compliant, it will be equipped with O2sensors before and after the catalyst. The O2 sensor that isdownstream of the catalyst is often referred to as the catalystmonitor because that is exactly why it is there—to enable the OBDsystem to monitor catalyst efficiency by comparing oxygen levelsbefore and after the catalytic converter.

Similarly, you can use the upstream/downstream O2 sensor pairsto test catalyst efficiency. If there is little or no oxygendownstream of the catalyst, that indicates good oxygen storagecapability and good catalytic converter efficiency.

In order to use the O2 sensors as diagnostic tools, you must firstensure that they are operating correctly (see “O2 Sensor Testing”on page 103). In order to test the operation of the downstream O2sensor, check its range and response when the catalyst is cold.MAKE SURE THAT BOTH THE RANGE AND RESPONSE OF BOTH O2SENSORS ARE NORMAL BEFORE PROCEEDING.

Once you are certain that the O2 sensors are operating normally,you can use the O2 sensor signals to diagnose the catalyst’s abilityto store oxygen and to perform efficiently. With a lab scopeconnected to an upstream O2 sensor on one channel, and adownstream O2 sensor on the second channel, compare theexhaust oxygen content before and after the catalytic converter.The differences between the two waveforms are indicative of thecatalyst’s ability to store oxygen and to perform efficiently.

The upstream O2 sensor waveform should be toggling whichindicates good closed-loop fuel control, while the downstream O2sensor should appear as a fairly steady, flat line (see Figure 25).In the example waveforms below, the upstream O2 sensor is onthe bottom trace (zero volts indicated by“1”) and the downstreamO2 sensor is on the top trace (zero volts indicated by “2”).

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Figure 25: O2 Sensor Waveforms at High Idle Indicating Good Catalyst

The voltage level of the downstream O2 sensor waveform willlikely be .7-.8 volts if the catalyst is not degraded at all (seeFigure 25). With some degradation, the voltage level will be closerto the mid-range point (around .5 volts). A more seriouslydegraded cat will result in the downstream O2 sensor waveformmirroring the upstream O2 sensor waveform (see Figure 26 onpage 113). This is because a degraded cat will have little effect onthe oxygen in the exhaust because it is not able to store and usethe available oxygen to convert CO and HC to CO2.

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Figure 26: O2 Sensor Waveforms Indicating Inefficient Catalyst

WHAT ABOUT USING OBD SCAN DATA?

You can also use OBD-II scan data to monitor O2 sensor pairs.However, when using scan data to monitor O2 sensor output, keepin mind these critical points:

• you must be certain of the O2 sensor’s ability to toggle

• the sample rate of the scan data is very limited compared to the DSO which displays the actual signal

• if the PCM recognizes a fault in the O2 sensor circuit, it may substitute a default value. If so, the scan data may display the substitute value rather than the actual O2 sensor value.

Because of the limitations of scan data, it isn’t always appropriatefor monitoring O2 sensor signals. Often it is best to do apreliminary check of all O2 sensor pairs using scan data, and then,if you have any doubts, connect your DSO to the suspect pair ofO2 sensors and re-run your test.

Given that you can perform this test on a road test, you candiagnose catalyst efficiency under conditions that mirror thedriving test on an AirCare inspection. Sometimes a degradedcatalytic converter will appear normal under no-load conditionssuch as idle and high-idle, but it cannot maintain efficientperformance when exhaust volume is higher such as it is when thevehicle is being driven. Using the OBD-II catalyst monitors asdiagnostic tools gives you the ability to monitor catalyst efficiencyunder those conditions.

For more examples on this method of testing catalyst efficiency,refer to the 2005 - #4 issue of the AirCare Repair newsletter.

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Induction System Testing

Induction System Basic Tests

A visual inspection for loose clamps and cracked rubber should bethe first step of any induction system testing. Don’t overlook thebasics and end up wasting a bunch of time and money.

The calibration of the engine’s fuel system is based on a certainamount of flow through the PCV system. Always check that thebreather filter is unrestricted and make sure that the PCV valve ororifice is correct for the application. When in doubt, use an OEMpart to ensure correct calibration.

Air/Vacuum Leak Testing

Vacuum leaks and un-metered air leaks are very common.However, they may or may not have a significant effect on vehicleemissions depending on where the leak is, how big the leak is, andhow well the PCM is able to compensate for the problem.

For example, a vacuum leak on an individual intake runner mayhave a large effect on one cylinder but not on the system as awhole.

On the other hand, an un-metered air leak between the throttleplate and the airflow sensor will affect all cylinders equally butmay or may not be severe enough to cause an increase inemissions.

The bottom line is that if you are diagnosing an emission failureand the cause is not obvious, you are going to have to be prettypicky with vacuum and air leaks. To be conclusive in testing theintegrity of the induction system, you are going to need to performthe tests described below.

Testing for vacuum/air leaks using air pressure and soapy water

With the engine off and the induction system pressurized with lowpressure compressed air, apply soapy water to suspect areas andwatch for the formation of bubbles.

Testing for vacuum/air leaks using propane

With the engine running at idle speed, apply propane to suspectareas while monitoring the CO content ahead of the catalyst or bymonitoring the O2 sensor voltage.

Depending on how you are monitoring for the propane being drawninto the engine and burned, you may have to check suspect areasseveral times to be sure. Remember that if the closed loop systemis active, it will make fuel system adjustments to compensate forany propane that is drawn into the engine through a leak.

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Testing for vacuum/air leaks using smoke machine

Smoke generating machines can also be used to visually identifyleaks by pressurizing induction systems with a thick smokemixture. With the engine shut off, connect the smoke output hoseto a large manifold vacuum port. Note that smoke will come out ofevery path where there is air flow so you will probably want tominimize the airflow out of known openings (such as the actual airinlet) to make things easier. This same method can also be usedfor exhaust system leaks as well.

NOTE: Some manufacturers have published warnings regardingthe maximum pressure that the induction system can withstandfrom smoke machines. If the machine you are using is capable ofgenerating pressure of more than .14 bar (2 pounds per squareinch) you should be cautious in its use.

Other Sources Of Un-metered Air

Incorrect PCV valve flow rate can also cause disruption of the air/fuel mixture. In some cases, it can also cause a lean shift that willinhibit the catalyst’s ability to reduce NOx. Make sure that youhave checked the PCV system for proper operation and correctapplication (see “Positive Crankcase Ventilation (PCV) Valve orOrifice” on page 116).

Ignition System Testing

Ignition System Basic Tests

While you are connecting your oscilloscope or ignition analyser,perform a visual inspection of spark plug and coil connections.

Use your timing light to ensure that the timing is set tospecifications. When checking initial advance, make sure you areprecise and that you are checking it under the operating conditionsspecified by the manufacturer.

Also when checking initial advance, make sure that you arecomparing the setting to the correct specification. If in doubt, callthe techline on models not covered in your repair manuals.

When checking advance mechanisms, you should check for brokensprings and pay particular attention to the freedom of movement.You should also look for signs of wear in the limiter slots thatdetermine the maximum advance.

Ignition Analyser/Oscilloscope Testing

With the required connections made for your oscilloscope orignition analyser, perform an analysis of the entire ignition systemto ensure that adequate spark energy and duration is availableunder all operating conditions. Remember that if you are

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diagnosing a driving HC problem, you must pay particularattention to ignition system operation under load. Practicallyspeaking, you should take a close look at the snap kV spark energyand duration.

If inadequate energy is available, check for excessive resistance inthe secondary circuits and check the primary ignition circuitsaccording to the manufacturer’s recommended procedures andspecifications.

High tension wire leakage can sometimes be detected by sprayingwater mist on wires and spark plug boots while looking for leakingspark or erratic ignition signals on the oscilloscope. Some techshave found that using a solution of one part ammonia and one partmethyl hydrate to eight parts water is more effective than usingstraight water for this purpose.

Crankcase Vapor Control System Testing

Positive Crankcase Ventilation (PCV) Valve or Orifice

The PCV system should first be checked to ensure that the fixedorifice or variable orifice valve is the correct size for theapplication.

• If the system uses a fixed orifice, check the size of the orifice using a drill bit and check with manufacturer’s specifications. If the correct size drill bit does not go through the orifice, you either have the wrong part or the orifice is plugged and needs to be cleaned out.

• When in doubt, a new OEM PCV valve ensures the correct calibration of the system.

• If the system uses a valve, you must check to ensure that it is operating correctly. Remove the valve from the engine and check for manifold vacuum at the valve with the engine running. Check for movement of the valve by placing your thumb over the end of the valve—you should be able to feel the internal valve move.

Crankcase Pressure and Oil Contamination

If the PCV system is operating correctly, you should then check toensure that excess crankcase pressure or contaminated oil is notcausing excessive CO emissions.

If CO emissions drop by more than 1.00% when the PCV orifice isdisconnected from the crankcase, excessive flow or contaminatedengine oil is indicated. Change the engine oil to ensure it is cleanand re-test.

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If the engine oil is not contaminated and the PCV valve or orifice iscorrect for the application, excessive crankcase vapors can only becaused by serious internal engine defects.

Evaporative Control System Testing

Visual Inspection of EVAP System Components

Vacuum lines, valves, and the charcoal canister should be visuallyinspected for signs of liquid fuel and cracks.

Functional Testing of EVAP System Components

Check for a saturated charcoal canister by crimping or otherwiseblocking the purge hose and monitoring the reduction in CO level.If the CO drops by more than 1.00%, a saturated canister isindicated.

Fuel System Testing

Carburettor (non-feedback) Tests

The vast majority of CO problems on carburetted vehicles arecaused by the carburettor itself. In most cases the problem can beremedied once it is pinpointed exactly where the fault lies.

There are quite a few things that can go wrong with carburettors.Therefore, there may be a lot of things that you will need to check:

• incorrect adjustment of idle mixture

• incorrect adjustment or operation of metering needle(s)

• incorrect adjustment or operation of float

• incorrect adjustment or operation of choke

• operation of power valve relative to engine load

• leakage of fuel from accelerator pump

• leakage of fuel from casting plugs

• leakage of vacuum from gaskets

• restriction of air bleeds and emulsion tubes

• wear of metering needle(s) and main metering jet(s)

A careful visual inspection is all that is required to check for mostof these possibilities. However, performing a visual inspection mayrequire disassembly of the carburettor.

Although there are a lot of things that can go wrong withcarburettors, you can often eliminate some of the possibilities justby reviewing the inspection data and applying some logic.

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Idle CO Bad But Driving CO Good?

If the vehicle failed for idle CO but is fine for driving CO, you don’tneed to worry about the power valve, accelerator pump, or chokecircuits. Check the idle mixture adjustment and main metering. Ifthe problem is intermittent you should also look into the possibilityof percolation of the fuel in the carburettor bowl.

Most idle CO problems on carburetted vehicles are caused by amal-adjusted carburettor. In some cases however, a carburettordefect will be the cause. You tell the difference by checking theadjustment using the manufacturer’s recommended procedure.

If you are not able to adjust the carburretor to specification, it islikely that an internal defect such as a restricted air bleed or aworn metering needle and/or jet is causing the mixture problem.This includes if the idle mixture adjustment is sealed—if this is thecase and idle CO is high, an internal problem is likely.

When checking or adjusting idle air/fuel mixture, it is criticallyimportant that the manufacturer’s adjustment procedure befollowed. The procedure may include setting certain test conditionssuch as idle speed, and enabling or disabling of various controlsthat ensure the specifications and adjustment are accurate.

Idle CO Bad and Driving CO Bad?

If the vehicle failed for idle CO and is also high for driving CO, youneed to check the float, main metering, power valve, acceleratorpump, and choke circuits. You will need to check the idle mixtureadjustment as well but don’t expect an adjustment of idle mixtureto correct a driving CO problem.

Depending on carburettor design, the most common causes ofexcessive CO both while driving and at idle are related to highfloat levels due to a saturated float or a leaking needle and seat.

Metering needles and jets can also be a problem. Many carbs havemetering needles that move in and out of metering jets. Both theneedles and the jets commonly wear out from this movement. Aclose visual inspection of the needles and jets is usually all it takesto identify this problem. Repair requires replacement of theneedles and replacement or resizing of the jets.

Not all carbs have metering needles though. If the carb doesn’thave metering needles, the jets can’t be worn out. However, thejets can be the incorrect size. In fact, this is extremely common,particularly if the carburettor has ever been replaced with a rebuiltunit or an aftermarket “performance” carb. Rebuilts are notoriousfor being calibrated too rich. If this is the case, it is recommendedthat you call the techline for assistance in determining andrestoring correct jetting. See “Obtaining Technical Assistance” onpage 133.

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Idle CO Good But Driving CO Bad?

A common cause of excessive CO only while driving (not at idle or2500 rpm no-load) is power enrichment cutting in too soon. Manycarbs have a power valve or power piston that is controlled by avacuum circuit and a spring to provide a rich mixture for heavyload conditions (usually seven inches of manifold vacuum). Anincorrect spring or a stretched spring can cause the valve to openat a lighter load than it should. A leak in the vacuum circuit thatcontrols the power valve, or any defect that causes engine vacuumto be lower than normal can also cause it to open prematurely.

On some Rochester and Carter carburettors you can quickly checkwhether the power valve is opening prematurely using thefollowing procedure:

1) connect a vacuum gauge to read manifold vacuum and go for a road test where you can simulate the ASM test

2) determine what the manifold vacuum is while cruising in 2nd gear at 40 kph up a slight grade

3) return to the shop and remove the access plug over top of the power piston

4) rest a plastic coffee stir-stick or similar lightweight stick on top of the piston

5) start the engine and load the engine to the same manifold vac-uum level as determined in step 2.

6) watch the stir-stick to see if the power piston is rising at the level of manifold vacuum that exists during the AirCare driving test.

Feedback Carburettor Tests

Many of the tests in the previous section also apply to feedbackcarburetted vehicles and, for the most part, the same logic can beused to narrow down the possibilities. However, the feedbacksystem adds several more considerations.

Most feedback carburettor systems should be in closed loopthroughout the driving test but some will use an open-loopstrategy at idle. Fault codes may be present in the PCM memoryand, if so, they may assist in pinpointing the cause of theemissions failure. However, a lack of fault codes does not rule outthe possibility of a defect in any aspect of the fuel managementsystem. Throttle switches, vacuum sensors, and switches cansometimes prevent closed-loop on feedback carburetted systems.

In many cases, feedback carburettor fuel control problems arecaused by either a defective or maladjusted carburettorcomponent, or a defective O2 sensor. After checking O2 sensorperformance, feedback carburettor system component testingshould be performed.

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Mixture-Control Devices

There are various types of mixture control devices used infeedback carburettors and various ways to test them. Most mixturecontrol devices are electrical solenoids which are prone tophysically sticking and electrical problems.

• First do a visual inspection of the electrical connector and associated wiring.

• Check the resistance of the solenoid and the electrical signal from the PCM.

• Look at O2 sensor voltage and mixture control solenoid duty cycle simultaneously to evaluate system response. Most manufacturer’s have specific test procedures that should be followed.

• Check the o-ring that seals the mixture control solenoid (while you are in there, you may as well replace the o-ring to be sure it is sealing).

• If the solenoid needs replacement and it is only available with the air-horn assembly or the entire carburettor you may be able to modify a solenoid for another vehicle to fit. For more info, refer to the AirCare Repair newsletters or call the techline.

Other mixture control devices may be vacuum controlled or acombination of an electrical solenoid and a vacuum operated valve.These are prone to typical vacuum circuit problems such as leakingdiaphragms, leaking o-rings, cracked hoses, etc. so you shouldalso include a visual inspection for these potential problems.

Refer to manufacturer’s recommended procedures for testingvacuum valves, bleed valves and solenoids, and other mixturecontrol components.

Fuel Injection System Tests

In most cases, fuel control problems are caused by a defective O2sensor. After checking O2 sensor performance, fuel injectionsystem component testing should be performed.

Fault codes may be present and, if so, they may assist inpinpointing the cause of the emissions failure. However, it isimportant to understand what the on-board computer is capable ofrecognizing in terms of faults. A lack of fault codes does not ruleout the possibility of a defect in any aspect of the fuelmanagement system.

Testing of each of the various components of a typical fuelmanagement system is discussed in the sections that follow.

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Remember that if the problem you are trying to diagnose (highemissions) is not present at the time you are performing thecomponent tests, you need to try to simulate the conditions underwhich the problem occurs.

For example, if you are diagnosing a driving CO problem and theairflow sensor output looks good at idle, that doesn’t mean thatthe airflow sensor is okay. To be sure that it is okay, you mustcheck it out under the same conditions that the problem occurs.

Airflow Sensor

You should check the airflow sensor electrically after you havechecked the induction system for air/vacuum leaks (see “InductionSystem Testing” on page 114).

VAF Vane-type air flow (VAF) sensors return a varying voltage to thePCM depending on the measured airflow. Some models output ahigher voltage with higher airflow and others output a lowervoltage for higher airflow.

For either type of VAF sensor check the following:

• check the voltage output and compare to manufacturer’s specifications.

• check the signal waveform using a DSO. Look for a clean and glitch-free voltage signal such as in Figure 27 on page 122.

• If the output is incorrect, check reference / supply voltage and ground circuits before condemning the sensor.

MAF Mass air flow (MAF) sensors may be varying voltage output orvarying frequency output. For varying voltage type MAFs performthe same checks as VAFs above. For digital MAFs (varyingfrequency) perform the following checks:

• check the frequency output using a frequency counter and compare to manufacturer’s specifications. If possible, you should also read the indicated airflow with a scanner and verify that the PCM is seeing the same thing that the sensor is indicating.

• check the signal waveform using a DSO. Look for a clean and glitch-free square wave signal.

If the output is incorrect, check reference / supply voltage andground circuits before condemning the sensor.

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Figure 27: MAF Voltage Output Waveform (Snap Throttle)

Hot-Wire MAF Cleaning If you are performing induction system testing on a vehicleequipped with a resistor type of hot-wire mass air flow (MAF)sensor, you should also visually inspect and clean the “hot-wire” inthe throat of the sensor. Experience has shown that the airflowindicated to the PCM by the MAF sensor is greatly influenced byeven the slightest deposits of dirt or oil on this sensor.

NOTE: This is only an issue on MAFs that use a resistor type ofsensing element. Cleaning is not recommended on hot-filmsensors or hot-wire sensors that have a built-in burn-off functionsuch as Bosch. You must be very careful when you are cleaning thehot-wire as it is extremely delicate. A cotton swab is anappropriate tool to use for cleaning.

It is a good idea to perform baseline measurements of the MAFsensor output linearity prior to cleaning. The procedure is outlinedin the next section. Additional information on the effects of dirtyMAF sensors can be found in the 2001-#2 issue of the AirCareRepair newsletter.

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MAF Sensor Linearity MAF sensor output problems are quite common and can cause arich or lean shift in fuel control under certain operating conditions.The output can be absolutely correct at idle and low speeds but beway out at higher speeds and loads. In other words, the output isnot linear.

To check for MAF sensor linearity you need to record the sensoroutput or airflow for each of a series of rpm increments. The rpmincrements should result in a linear increase in output. A graphicexample is shown in Figure 28. Note that the measured outputcould be in voltage, frequency, or grams per second.

Figure 28: MAF Sensor Linearity Check

Linear output means that for each increase of 200 rpm, the outputshould increase by an equal amount. Let’s say that the sensoroutput is 1.2 volts at 1000 rpm and increases to 1.3 volts at 1200rpm. You should expect an increase of .1 volts for each 200 rpmincrease.

If in doubt, do a baseline measurement of the MAF output and thelong-term fuel trim at exactly 2500 rpm. Then clean the MAF (seethe caution on page 122) and re-check at exactly 2500 rpm. If theindicated airflow increased and the long-term fuel trim decreased,that means that the MAF was under-predicting airflow prior tocleaning.

800

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Indicated Air Flow(volts, frequency, or grams per second)

Engi

ne R

PM

This abnormal pattern clearlyindicates that the indicated airflowdoes not increase linearly with enginespeed. This can be caused by a dirtyhot wire or a faulty MAF sensor.

This normal patternindicates the relationshipbetween engine speed andindicated airflow is linear.

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MAP Sensor

Depending on design, MAP sensors may return a varying voltage orvarying frequency to the PCM to indicate engine load. To test aMAP sensor, perform the following tests as appropriate:

• check the voltage output or frequency output and compare to manufacturer’s specifications. If possible, you should also read the indicated manifold pressure with a scan tool and verify that the PCM is seeing the same thing the MAP sensor is indicating.

• check the signal waveform using a DSO. Look for a clean and glitch-free square wave or straight voltage signal depending on sensor type.

If the output is incorrect, check the manifold vacuum at thesensor, and check the reference (supply) voltage and groundcircuits before condemning the sensor.

Coolant Temp Sensor

Most coolant temperature sensors (CTS) operate the same and aretested the same:

• check the indicated coolant temperature either by measuring resistance or voltage (with sensor connected), and compare to manufacturer’s specifications.

• if possible, read the indicated temperature with a scan tool. If the output is incorrect, check the reference (supply) voltage and ground circuits and coolant level before condemning the sensor. A poor ground connection will result in the PCM thinking that the engine is colder than it actually is. Also, if the CTS is not immersed in coolant it will indicate that the engine is much colder than it actually is. This could result in a rich condition that may be intermittent.

Air Temp Sensor

Most air temperature sensors (ATS) operate the same and aretested the same:

• check the indicated intake air temperature either by measuring resistance or voltage (with sensor connected), and compare to manufacturer’s specifications.

• if possible, read the indicated temperature with a scan tool. If the output is incorrect, check the reference (supply) voltage and ground circuit before condemning the sensor. A poor ground connection will result in the PCM thinking that the intake air temperature is colder than it actually is. This could result in a rich condition that may be intermittent.

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Throttle Position Sensor

Most throttle position sensors (TPS) operate the same and aretested the same. However, some will combine throttle switcheswith the sensor. For more on throttle switches, see page 126.

Sensors should be checked by measuring signal voltage (with thesensor connected), and if possible, reading the indicated throttleopening on a scan tool. Compare to manufacturer’s specifications.

Because throttle position sensors are potentiometers, theycommonly wear out or become intermittently glitchy. For thisreason, if the symptoms are erratic you should test the TPS withyour DSO before concluding that it is okay.

To perform a TPS sweep test using your DSO:

1) Locate the TPS signal wire and connect the DSO signal probe.

2) Connect the COM probe to the engine block.

3) Turn the key on and move the throttle throughout its range using the accelerator pedal.

4) Monitor the DSO waveform while opening and closing the throt-tle a number of times and wiggling it at various throttle open-ings. The waveform should be a straight line with a smooth transition whenever the throttle is moved. When the throttle is quickly snapped open and released, the signal should look like the waveform shown in Figure 29. Any spikes that are evident in the waveform indicate a bad TPS.

Figure 29: TPS Voltage Output Waveform (Snap Throttle)

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Throttle Position Switch

Some vehicles don’t use a variable resistor to indicate throttleposition but instead use two microswitches to indicate only closedthrottle and full throttle conditions. The two switches may shareone housing.

Throttle position switches should be tested using themanufacturer’s test procedure and specifications. Using avoltmeter to check continuity of the switch contacts is thepreferred method.

Other Fuel System ProblemsLEAKING INJECTOR? Leaking injectors may be the cause of HC and/or CO problems.

Throttle body injectors are usually easy to observe for dripping. Ona port fuel injected engine, if you suspect that an injector may beleaking, you can perform a system rest pressure test and/or aninjector balance test.

Most manufacturers have published specifications for systempressure including a time factor for how long the system shouldmaintain a certain pressure following shut-down. If an injector isleaking, system pressure will deteriorate quicker than normal aftershut-down.

An injector balance test involves disabling each injectorindividually and monitoring the rpm drop or power contribution ofthat cylinder. If an injector is leaking there will continue to besome combustion in that cylinder, even when the injector isunplugged, and the rpm drop won’t be as significant as the othercylinders. As with all power balance tests performed with theengine running, you must prevent the system from compensatingfor changes made during the test (stable vacuum to MAP sensor,etc.). For more information see “Power Balance Testing” onpage 130.

Another method of injector balance test can be performed using apulse tester to open an individual injector while monitoring fuelrail pressure. A leaking or restricted injector will cause lesspressure drop compared to other injectors.

RESTRICTED INJECTOR? Restrictions and poor spray patterns result in NOx and/or HCproblems. Depending on how bad it is, a restricted injector can bemuch harder to identify. For diesel injectors, bench testing is theonly method of ascertaining that an injector orifice is notrestricted. For non-diesels, without removing the injector(s) andrunning them on a test bench, it can be very difficult to ascertainthat an injector has a poor spray pattern.

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Therefore, using the process of elimination is certainly wise in thiscase and you should check all other possible causes before you tryand determine that the injectors are restricted.

Other than removing and bench testing the injectors, the bestmethod for detecting spray pattern deficiencies is by powerbalance testing. There are two methods of power balance testingthat can help to diagnose and isolate a restricted injector: the HCper cylinder power balance test and the CO per cylinder powerbalance test.

To identify port fuel injectors with poor spray patterns using theHC per cylinder method, you monitor engine-out HC when theignition is disabled to an individual cylinder. If an engine hasexcessive HC, and one cylinder is responsible for the excessive HCbecause of a poor spray pattern, the amount of HC increase whenyou kill the spark to that cylinder will be less than the othercylinders.

To identify port fuel injectors with poor spray patterns using theCO per cylinder method, you should monitor engine-out CO whenthe injector connector is disconnected on an individual cylinder. Ifan injector is restricted, the amount of CO decrease when youdisable that injector will be less that the other cylinders.

Don’t forget, with all power balance tests performed with theengine running, you must prevent the system from compensatingfor changes made during the test. For more information see“Power Balance Testing” on page 130.

Propane or Natural Gas Fuel System Tests

Early propane and natural gas systems that operate in open loopare typically lean calibrations with engine-out CO levels of lessthan .50% while driving.

If the vehicle is producing excessive CO emissions during thedriving portion of the AirCare inspection, perform pressureregulator tests as per manufacturers recommended proceduresand specifications. On variable venturi systems evaluate mixercondition only after ensuring you have proper regulator operation.

Closed-loop alternative fuel systems require correct inputinformation and output device operation to function properly. As afirst step in diagnosing any emissions failure on these systems it isusually most efficient to start by observing the O2 sensor withyour lab scope while simultaneously monitoring the device whichcontrols the air/fuel ratio. This is typically a solenoid controllingthe pressure regulator on variable venturi systems and a steppermotor in the dry-gas hose in fixed venturi systems. Some of themore sophisticated systems will also perform self-diagnostics and

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generate trouble codes to assist the repair technician. Followmanufacturers diagnostic procedures where available.

Air Injection System TestingIf you are diagnosing a NOx failure, you should check the airinjection system to make sure that air isn’t being injected when itshouldn’t be. Excessive CO could also result if air is being injectedupstream of the O2 sensor when in closed loop.

If you are diagnosing an HC or CO problem and the system ismeant to be injecting air under the conditions when the emissionsare high, you should perform the following tests:

• First check to see whether the system is working at all: crimp or block the air injection hose(s) under a condition when there is supposed to be air injection and monitor the reduction in O2 and the increase in CO and HC. You should see a significant difference in HC and CO. For pulse air systems you should see an O2 decrease of at least 2% with the pulse air system disabled. For pump type air injection systems you should see an O2 decrease of at least 5% with the air injection disabled.

• Check the air injection controls such as gulp valves, bypass solenoids, and diverter solenoids using the manufacturer’s recommended procedures and specifications.

EGR System Testing

EGR System Basic Tests

The first thing you should check on every EGR system is theexhaust passage. Adequate exhaust gas must be available to theEGR valve for the maximum flow (highest load) conditions. In mostcases you can test this by manually opening the valve at idle andstalling the engine. If the engine does not stall, it should drop byat least 300 rpm. Otherwise, you probably have a restriction in theexhaust passage or pipe.

EGR Valves

• Test the EGR valve for proper movement by applying vacuum to the diaphragm. If the valve does not open with vacuum applied you may have a defective valve or you may have a backpressure modulated valve. Before condemning the EGR valve, you must perform further testing using the manufacturer’s recommended procedure.

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• You also must make sure that the EGR valve completely seals the exhaust passage from the intake manifold when the valve is closed. Leaking seats may cause excessive HC emissions at idle. Oftentimes the only way to be absolutely sure that the valve is not leaking is to remove the valve for visual inspection.

• Some vehicles use no external EGR control devices at all but instead use one or more electrical solenoids to directly control exhaust gas recirculation. On these systems you need to check each of the solenoids for proper operation electrically and also for physical defects such as sticking open or seized shut.

EGR Controls

Many different controls are used in various types of vehicles tocontrol and monitor the operation of the EGR valve. In manycases, you will need to refer to the manual for the specific vehicleto troubleshoot the EGR controls. However, some generalprocedures are shown below.

• Pressure feedback sensors and modulators should be checked for any blockage or restriction in the backpressure sensing tube.

• Pressure feedback sensors should be checked electrically for proper reference voltage, ground, and signal return to the PCM.

• EGR valve position sensors should be checked electrically for proper reference voltage, ground, and signal return to the PCM.

• EGR temperature sensors should be checked for proper reference voltage and ground. Temp sensors should also be checked for correct resistance using the manufacturer’s specifications.

• EGR vacuum control solenoids should be checked for the correct pulsed voltage and ground. Solenoids should also be checked for correct resistance using the manufacturer’s specifications.

• Venturi vacuum amplifiers should be checked for correct vacuum input and output using the manufacturer’s recommended procedures and specifications.

• Thermostatic vacuum switches should be checked to ensure they switch states and allow vacuum to pass through only when the engine is warm (or vice-versa for some switches). Also, remember that a low coolant level may prevent correct operation of any temperature sensor or switch.

• All associated vacuum hoses and fittings should be checked for cracks, leakage, and secure connections.

• The exhaust system should be checked for modifications which may be adversely affecting exhaust backpressure and the control of the EGR.

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Engine Integrity Tests

Power Balance Testing

A power balance test can be useful in identifying uneven powercontribution amongst all cylinders. To be effective, a powerbalance test must be preceded by other more basic testing. Forexample, don’t try and diagnose an HC problem with a powerbalance test if you haven’t already completed the ignition systemstests, and fuel control tests.

A power balance will be most effective as a diagnostic tool if youperform the test under the same operating conditions as when theproblem is occurring. For example, if you are diagnosing a vehiclethat failed for HC at idle, don’t do your power balance at 2000rpm. Low speed problems such as a leaking EGR valve will not beevident above approximately 1500 rpm. Conversely, problems suchas weak or broken valve springs may not be evident at idle speed.

To be effective, you must do the power balance test with a stablebaseline rpm. An engine that is surging by 100 rpm is not going torespond very consistently when individual cylinders are disabled.

Also you should try and minimize the ability of computer controlsand other devices from affecting the rpm and the stability of theengine. For example, electric cooling fans, idle-speed controlmotors and solenoids, air conditioning compressors, and sparktiming controls can all render power balance tests invalid. You caneliminate these factors by disconnecting the component (O2sensor, idle speed control, cooling fan, etc.). Be very cautious notto overheat the engine if you disconnect the electric cooling fan forpower balance testing. An external cooling fan should always beused.

If the test reveals any uneven power output between cylinders(that is not the result of the computer making adjustments whileyou are performing the power balance), compression testing andcylinder leakage testing should be done to check mechanicalintegrity on the suspect cylinder(s).

If there is no cylinder leakage, the low power contribution must bedue to a valvetrain problem. Remember, fuel, ignition, andinduction systems were already checked out before doing thepower balance test. If you did not perform those tests first, yourdiagnostic conclusion will be inaccurate.

Compression Test and Cylinder Leakdown Test

Once a poor performing cylinder is identified, a compression testshould be performed. Variation in compression pressure should beno more than 10% from cylinder to cylinder.

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If compression is low, a cylinder leakdown test can be a big help inpinpointing where the compression is being lost. Be very carefulwhen performing these tests. Disable the ignition to prevent anysparks and disable the fuel pump to ensure the engine doesn’t getflooded. Never put your hand near the drive belts or belt drivenaccessories when you have compressed air applied to a cylinder.

Combustion Chamber Deposits

Unless you have a boroscope to view inside a cylinder, you cannotconclusively test for excessive carbon deposits in a combustionchamber. Therefore the only logical process to follow is toeliminate all other possibilities first. Only then is it reasonable toconclude that combustion chamber deposits are contributing toexcessive NOx emissions.

Many techs have had good success with combustion chambercleaning chemicals if applied correctly. Generally, you should apply500 ml (some manufacturers recommend more) of the combustionchamber cleaner through a large vacuum hose, stalling the engineafter all of the cleaner has been induced into the engine, it iscritical that you leave it soak overnight before restarting theengine. For more information, refer to the 1997-#4 issue of theAirCare Repair Newsletter.

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Chapter 9Obtaining Technical

Assistance

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Chapter 9 - Obtaining Technical Assistance

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Contacts At PVTT

AirCare TechLineCertified technicians are able to obtain assistance from PVTTtechnical staff if they encounter difficulties diagnosing or repairingvehicles that have failed their AirCare inspection.

Technicians are encouraged to call Ron or Brad between 8:00 a.m.and 4:30 p.m. Monday to Friday at the numbers below.

Ron Leavitt, Emissions Technical Advisor - 604-453-5163

Brad Coupland, Emissions Testing Specialist - 604-453-5172

RepairNet HelpAdrian Yee, Program Policy Analyst - 604-453-5165

Technician and Repair Centre CertificationConnie Hajdik, Certification Clerk - 604-453-5152

AirCare Program & Certification PolicyPeter Hill, Manager, Program Policy - 604-453-5167

Adrian Yee, Program Policy Analyst - 604-453-5165

Program AuditorTim Jollimore, Program Auditor - 604-453-5159

Other Sources of Information and AssistanceAirCare RepairNet provides certified technicians with access todetailed inspection and repair data including second by secondemissions readings. For more information, see the RepairNet UserGuide and Chapters 4 and 6 of this manual.

The International Automotive Technicians Network (iATN) has alsobeen found to be a useful resource for emissions repairtechnicians. Remember, emissions testing programs are in use inmany other jurisdictions besides the Lower Fraser Valley, so youmay benefit from sharing experiences and knowledge withtechnicians in other areas.

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Chapter 10Repair Cost Estimates

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Chapter 10 - Repair Cost Estimates

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The Importance Of Your Repair Cost EstimateOnce you have completed your diagnosis, it is very important toproperly itemize and document each aspect of the estimate for anumber of reasons:

• it will be easier to explain the results of your diagnosis to your customer;

• it will be easier for the customer to understand what is required to repair the vehicle;

• should your customer decide to not authorize all of the needed work, the estimate becomes a record of what they must eventually get repaired;

• a written estimate will minimize the potential for disputes when it comes time to pay the bill; and

• it reduces the possibility of errors if other staff are responsible for transcribing information to the work order.

What To Include In Your Repair Cost EstimateA proper estimate of repair costs should include:

• the cost of diagnosis

• the cost of each part that needs replacement

• the cost of labour to perform each part of the repair

• the taxes, levies, shop supplies, and any other fees that form part of the total bill payable by the customer.

Revising Your EstimateYou should make sure that your customer understands your shop’spolicy for obtaining authorization to go ahead with any additionalwork beyond what was initially approved. For example, if approvalover the telephone is considered acceptable or not.

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Chapter 11Repair Cost Limits

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Chapter 11 - Repair Cost Limits

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Understanding Repair Cost Limits

Why Repair Cost Limits ExistThe air quality benefits derived from the AirCare program onlyoccur if emissions defects are repaired. Unfortunately, noteveryone is adequately prepared financially for major repairexpenses. The repair cost limit / conditional pass system wasimplemented as a way of balancing economic and environmentalconsiderations.

In the event that a vehicle needs repairs that will cost more than acertain amount, the motorist has the option of obtaining aconditional pass which allows them to re-license their vehicle eventhough it is not completely repaired. The motorist is expected tohave the emissions defect(s) repaired as soon as they are able to.

How The Repair Cost Limits WorkThe repair cost limit is a dollar amount that is used to determinewhat repairs (if any) must be completed before the vehicle iseligible for a conditional pass. Once the diagnosis of a failingvehicle is complete and the needed repairs have been estimated,the cost(s) of repairs can be compared to the applicable repaircost limit to determine which repair(s) must be completed.

Repairs that can be done without exceeding the repair cost limitmust be done. If the motorist chooses not to authorize completionof those repairs, you must not submit repair data.

If the motorist chooses to authorize only those repairs that can becompleted without exceeding the repair cost limit, you mustsubmit repair data following completion of those repairs. Decidingwhich repairs to do when only partial repairs are authorized by thecustomer should be based on emissions reduction potential andcommon sense.

If the motorist chooses to authorize all needed repairs, even if thecost exceeds the repair cost limit, you must submit repair datafollowing completion of those repairs.

A common misconception about the repair cost limits is that theyspecify a minimum amount that the customer must spend to obtaina conditional pass. This is incorrect. The minimum amount that acustomer must spend is determined by what repairs the vehicleneeds.

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Using Repair Cost Limits

Examples Of How The Repair Cost Limits ApplyThe repair cost limit is a maximum amount that a motorist couldbe required to spend, depending on what repairs their vehicleneeds. To illustrate this, let’s use some examples;

EXAMPLE 1 Entire Repair Within Cost Limit

A 1979 car ($300 repair cost limit) needs a new EGR valve(estimated total cost of diagnosis and repair = $200). This repairfalls within the cost limit so it must be done before submittingrepair data. If the customer chooses not to authorize this repairyou must not submit the repair data.

The customer is required to replace the EGR valve because therepair can be done without exceeding the repair cost limit.

EXAMPLE 2 Partial Repair Within Cost Limit

A 1979 car ($300 repair cost limit) needs a new EGR valve andintake manifold gaskets (estimated total cost of diagnosis andrepair = $400). The entire repair does not fall within the cost limit.However, partial repairs can be done within the cost limit so itmust be done before submitting repair data. If the customerchooses not to authorize this repair you must not submit the repairdata.

The customer is required to replace the EGR valve because therepair can be done without exceeding the repair cost limit. Thecustomer is not required to replace the intake manifold gasketsbecause that would push the total repair cost over the repair costlimit.

EXAMPLE 3 No Repair Within Cost Limit

A 1979 car ($300 repair cost limit) needs a valve grind (estimatedtotal cost of diagnosis and repair = $1000). This repair does notfall within the cost limit and only one repair is needed so thecustomer is not required to have any repair completed. If thecustomer chooses not to authorize completion of this repair, thediagnostic fees are still payable. In this case you must submit therepair data.

The customer is not required to repair anything because the burntvalve is the only defect and it cannot be repaired withoutexceeding the repair cost limit.

Remember, the repair cost limit is a maximum and not a minimum.

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Current Repair Cost LimitsThe repair cost limits are specified in the British Columbia MotorVehicle Act Regulations (MVAR). The schedule to MVAR Section40.08(2) specifies the applicable limits by model year for non-tampering and tampering.

* For the application of repair cost limits, tampering is determined by the AirCare inspection centre.

NOTE: the tampering repair cost limit specified in the MotorVehicle Act Regulations for 1987 and older vehicles is as shownabove (no limit). However, this is not applicable because only 1988and newer vehicles are checked for tampering.

Table 4: Repair Cost Limits (no tampering identified)

Model Year Cost Limit

Pre 1981 $300

1981-1987 $400

1988-1991 $500

1992-1998 $600

Post 1998 no limit

Table 5: Repair Cost Limits (tampering identified*)

Model Year Cost Limit

Pre 1981 no limit (see note)

1981-1987 no limit (see note)

1988-1991 no limit *

1992-1998 no limit *

Post 1998 no limit *

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Chapter 12Complete Repairs

vs. Partial Repairs

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Chapter 12 - Complete Repairs vs. Partial Repairs

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The Problems With Incomplete RepairsThe intent of emissions diagnosis and repair is to identify andrepair all of the defect(s) that have an effect on a vehicle’sexhaust emissions. A conditionally passed vehicle is a vehicle thatis still in need of repairs.

Some may think that a conditional pass is as good as a pass but itis not. Although a conditional pass allows the vehicle to be re-licensed, the renewal transaction must occur prior to the 90-dayexpiry date. After 90 days the vehicle will require an AirCareinspection prior to re-licensing. That is not to say that the existinglicence will suddenly expire, it just means that a new licensingterm cannot begin after 90 days. If a vehicle is sold, or for anyother reason needs a change in the licence and insurance policy, itwill not be allowed.

The other problem with incompletely repaired vehicles is that therepair probably won’t have much of a positive effect on your repaireffectiveness index (REI). For more details on the effects ofconditional passes (cost waivers and qualifying waivers) on yourREI see “The Repair Effectiveness Index” on page 22.

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Obtaining Repair Authorization

Helping Your CustomerMany defects that affect exhaust emissions also have an effect onfuel consumption. A “dirty” vehicle is often an inefficient vehicle.In fact, the cost of repairing an emissions defect has the potentialto save money over time. This should be explained to yourcustomer to assist them in making the best decision regarding theauthorization of repairs.

When explaining to your customer the benefits of repairing anemissions defect, a further point that should be made is thatdriveability problems may result from partially repairing thevehicle. To optimize the vehicle’s balance of emissions, fueleconomy, and performance, all repairs should be completed.

Helping YourselfMost techs take great pride in all the work that they do and wantto do the best job possible. In automotive repair work, how good ajob the tech has done is often indicated by how pleased the bossand the customer are. However, when it comes to AirCare repairs,a third factor indicates the effectiveness of the repair in terms ofemissions reduction—the Repair Effectiveness Index (REI).

Complete details of the REI can be found in the section titled “TheRepair Effectiveness Index” beginning on page 22 of this manual.

If a motorist chooses not to authorize complete repairs it will nothave an adverse effect on a technician’s REI. However, becausethe best REIs result from the greatest reductions in emissions,obtaining authorization for complete repairs is bound to help thetechnician’s REI also.

It is in everyone’s best interest that emissions defects be repairedproperly and completely.

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Chapter 13The Repair Data Form (RDF)

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The Importance Of The Repair Data FormThe RDF is used by technicians to document the relevant details oftheir diagnosis and repair of vehicles that have failed their AirCareinspection.

It is mandatory for AirCare Certified Repair Centres to submitrepair data for every vehicle that they perform AirCare repairs on,and, the data must be submitted prior to the vehicle beingretested. The only exceptions are when you do not charge for adiagnosis, or when your customer refuses to authorize neededemissions repair that do not exceed the cost limit.

Repair details are important for a number of reasons. Whencompiled together, the data can be useful for setting repair costlimit amounts, estimating program benefits, settling disputes, andevaluating the effectiveness of different repair actions.

AirCare Certified Repair Centres submit repair data usingRepairNet (http://repairnet.aircare.ca). When the RDF iscompleted and submitted, a Repair Data Confirmation Form isgenerated for you to print and give to your customer. This papercopy of what you submitted electronically is for the customer’srecords. It may also be needed as proof of repairs in the event ofcommunication problems between the RepairNet database server,the inspection centre’s computer network, and the ICBC vehicleregistration database. Don’t forget to print this Repair DataConfirmation Form and give it to your customer!

Another benefit resulting from the collection of repair data is thatRepairNet allows you to review the repair history of each vehicle.This history is comprised of the actual data that techs havesubmitted in the past. For more information on accessing avehicle’s repair history, see the RepairNet User Guide.

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How To Complete The RDF on RepairNetDetailed instructions on all aspects of RepairNet can be found inthe RepairNet User Guide. Information regarding completion of theRDF is repeated below. For all other aspects of RepairNet, see theUser Guide.

The RDF is accessible on RepairNet only when you are logged onwith technician and repair centre credentials and have entered aregistration number for the vehicle you are working on.Information identifying the technician and repair centre isautomatically part of the submitted data so you don’t have toenter it anywhere on the RDF.

Much of the data entry is simply a matter of selecting one of therepair action choices from a pull-down menu. The choices availablefrom the pull-down menu will vary depending on the item but maybe any of the following:

D - Defective but not repaired

S - Serviced, adjusted, or reconnected

M - Missing

R - Replaced

NOTE: In cases where more than one of these choices areapplicable (partial repairs were performed but further work is stillneeded on the same component), you should select “D” from thepull-down menu and, in the “General Comments” section at thebottom of the RDF, enter details of the partial repairs that wereperformed.

No selection (blank) indicates that the component is okay or notapplicable to the emissions repair. This means that either thecomponent has been tested and is working properly, or thecomponent has nothing to do with the failure, or the componentnever existed on this vehicle.

To enter repair data follow this procedure:

1) Log on to RepairNet using both technician and repair centre cre-dentials (to find out how see the RepairNet User Guide).

2) Enter the registration number for the vehicle.

3) Select Submit Repair Data from the Repair Data drop-down menu.

4) Enter the applicable data in the “Repair Information” block.

5) Enter the applicable data in the other blocks as appropriate.

NOTE: You only need to enter the data that is relevant to therepair. All repair items that are left blank will default to OK/NotApplicable in the database.

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6) After all repair data has been entered, move your mouse pointer to the "Submit Repair Data" button at the bottom of the form and click the left mouse button.

A Repair Data Confirmation Form will then be displayed on thescreen. At this point you must print out a paper copy of the RepairData Confirmation Form to give to your customer.

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More Details on Each Section Of The RDF

Vehicle Information Completion of this section of the RDF is mandatory for all vehicles.

Estimated Cost

This is the total estimated costs including taxes for all repairs(parts and labour) to bring the vehicle into full emissionscompliance. Note that this estimate should include all costs for thework you have completed to this point (since the vehicle failed its’AirCare inspection), plus all additional costs that will be necessaryto fully repair the vehicle's emissions problem(s). The allowablevalues are 0 - 9999. Do not enter a dollar sign, decimals, or anycents.

Actual Parts Cost

This is the total parts cost including taxes for repairs that you havecompleted to the vehicle. The allowable values are 0 - 9999. Donot enter a dollar sign or any cents.

Actual Labour Cost

This is the total labour cost for repairs that you have completed tothe vehicle. The allowable values are 0 - 9999. Do not enter adollar sign, decimals, or any cents.

Work Order No.

Enter your shop's work order for the vehicle you are working on.The allowable values are up to 10 alpha-numeric characters.

Warranty

In this context, warranty can mean either a vehicle manufacturer’swarranty, an after-market warranty, or your shop’s warranty onrepairs previously attempted.

If emissions repairs were performed that were covered underwarranty, click in this box (a tick mark will appear). In this case,the "Estimated Cost" total should be what the total costs wouldhave been if their were no warranty coverage. The "Actual PartsCost" and "Actual Labour Cost" should be zero unless there wereadditional emissions repairs performed that were not coveredunder warranty.

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O2 / AF Sensor(s) If the vehice is equipped with one or more O2 sensors, and thevehicle is older than 1998 model year, you must enter diagnosticinformation for the oxygen sensor(s) on the vehicle both beforeand after repair. If the vehicle is 1998 or newer, completion of thissection is optional but should be completed if the O2 sensors arerelevent to the repair.

The reason for the requirement to measure and record O2 sensorvalues is that the vast majority of ineffective emissions repairs aredue to the technician failing to examine the performance of theclosed loop system using a conclusive diagnostic procedure. This isby far the number one cause for erratic emissions readings,inconsistent test results, customer complaints, and comebacks.

Refer to “O2 Sensor Testing” on page 103 of this manual fordetailed O2 sensor testing procedures.

Maximum Voltage

Record the highest voltage that the O2 sensor is capable ofgenerating. Note that the voltage fields are separated into voltsand millivolts. However, if the measured maximum voltage is lessthan 1 volt, leave the volts field blank and enter the millivolts inthe millivolts field.

The allowable values for the volts field are 0 - 9.

The allowable values for the millivolts field is 0 - 999.

In the case of wide band air fuel sensors, enter zero in the voltsfield and enter the measured maximum current output in themillivolts field.

Minimum Voltage

Record the lowest voltage that the O2 sensor is capable ofgenerating. Again, the voltage fields are separated into volts andmillivolts.

The allowable values for the volts field are 0 - 9.

The allowable values for the millivolts field is 0 - 999.

In the case of wide band air fuel sensors, enter zero in the voltsfield and enter the measured minimum current output in themillivolts field.

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Cross Counts

Record the number of times in a 10 second period that the O2sensor voltage crosses the mid-point of its range (450 millivolts).Each upslope or downslope that crosses the mid-point should becounted as one cross count. This measurement should be madeafter 30 seconds with the engine operating at 2500 rpm. Theallowable values for this field are 0 - 99.

In the case of wide band air fuel sensors, enter zero in the CrossCounts field.

Response Time

Record the slowest amount of time (in milliseconds) that it takesfor the voltage to rise from 300 millivolts to over 600 millivolts, orto drop from 600 millivolts to less than 300 millivolts. Theallowable values for this field are 0 - 999.

In the case of wide band air fuel sensors, enter zero in theResponse Time field.

Repair Actions At least one item in the “Repair Actions” section of the RDF ismandatory for all vehicles. For each component or system, indicatethe appropriate repair action. Repair actions options may includeone or more of the following:

R - replaced

S - serviced, adjusted, or reconnected

D - defective but not repaired

M - missing

Air Induction System

If you have identified and/or repaired an emissions relateddefect(s) on any component of the air induction system, select theappropriate repair action for that component. The allowable valuesare R, S, or D.

Cleaning a heat riser passage and re-attaching a stove pipe areexamples of where “S” is an appropriate selection in this category.

Catalytic Converters

If you have identified and/or repaired a catalytic converter defect.select the appropriate repair action for that component. Theallowable values are R, S, D, or M.

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Computer Controls General

If you have identified and/or repaired an emissions relateddefect(s) on the computer controlled engine management system,select the appropriate repair action for that component. Theallowable values are R, S, or D.

This section includes the Powertrain Control Module (PCM),diagnostic troubles codes (DTCs), and EEPROM. If you haveidentified and/or repaired an emissions related defect(s) on acomputer controlled engine management system that is nototherwise described on the RDF, select the appropriate action inthis section.

NOTE: specific input and output components are listed underdifferent headings on the RDF.

Computer Controls - Inputs

If you have identified and/or repaired an emissions relateddefect(s) on one or more of the inputs to the powertrain controlmodule (PCM), select the appropriate repair action for thatcomponent. The allowable values are R, S, or D.

Setting the TPS minimum voltage is an example of where “S” is anappropriate selection in this category.

Computer Controls - Outputs

If you have identified and/or repaired an emissions relateddefect(s) on one or more of the outputs from the powertraincontrol module (PCM), select the appropriate repair action for thatcomponent. The allowable values are R, S, D, or M.

Adjusting mixture control solenoid lean-stop and re-connecting theair injection diverter solenoid are examples of where “S” is anappropriate selection in this category.

Cooling System

If you have identified and/or repaired an emissions relateddefect(s) on the cooling system, select the appropriate repairaction for that component. The allowable values are R, S, or D.

Topping up coolant level and tightening coolant hoses areexamples of where “S” is an appropriate selection in this category.

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EGR System

If you have identified and/or repaired an emissions relateddefect(s) on the exhaust gas recirculation (EGR) system, selectthe appropriate repair action for that component. The allowablevalues are R, S, D, or M.

Cleaning out the EGR passage or re-connecting an EGR vacuumhose are examples of where “S” is an appropriate selection in thiscategory.

Emissions Controls - Other

If you have identified and/or repaired an emissions relateddefect(s) on any emission control system other than the EGRsystem, select the appropriate repair action for that component.The allowable values are R, S, D, or M.

Cleaning the PCV orifice and re-connecting the purge hose areexamples of where “S” is an appropriate selection in this category.

Engine Mechanical

If you have identified and/or repaired an emissions relateddefect(s) on the engine itself, select the appropriate repair actionfor that component. The allowable values are R, S, or D.

Applying combustion chamber cleaner and adjusting valveclearance are examples of where “S” is an appropriate selection inthis category.

Evaporative Control System

If you have identified and/or repaired an emissions relateddefect(s) on the cooling system, select the appropriate repairaction for that component. The allowable values are R, S, or D.

Topping up coolant level and tightening coolant hoses areexamples of where “S” is an appropriate selection in this category.

Fuel Delivery System

If you have performed adjustments or identified and/or repairedan emissions related defect(s) on any fuel system component,select the appropriate repair action. The allowable values are R, S,or D.

Cleaning throttle plates, setting minimum air rate (adjustingthrottle plates), and cleaning injectors are all examples of where“S” is an appropriate selection in this category.

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Ignition System

If you have identified and/or repaired an emissions relateddefect(s) on any component of the ignition system, select theappropriate repair action for that component. The allowable valuesare R, S, or D.

Remember that “S” is for serviced, adjusted, or reconnected.Overhaul of a centrifugal advance mechanism, adjustment of initialtiming, and reconnection of a spout connector are all examples ofwhere “S” is the appropriate selection.

Additional Diagnostic / Repair Details Any additional comments or information related to diagnosis andrepair can be entered in the "General Comments" section of theRDF. The fields are limited to 80 characters but three fields areprovided in case you want to enter more information.

The general comments section is not meant to be used by itself toindicate a defective item. It is meant only as a means to provideadditional information relating to the diagnostic and repair actionsidentified on the RDF. For example, if the vehicle has acompression problem, select “D” for Compression under the EngineMechanical section of the RDF and then enter the compressionvalues in the General Comments section. Do not use the GeneralComments section by itself to indicate a diagnostic or repairitem.

The General Comments section can also be used to indicate partialrepairs that were completed but have also been entered asdefective but not repaired. For example, if you cleaned the AirFlow Sensor but then it proved to be defective, you would select“D” for the Air Flow Sensor and enter a comment like “Cleaned AFSbut it is still not working correctly so will require replacement.”

The Repair Data Confirmation FormOnce the RDF is submitted, a Repair Data Confirmation Form isgenerated for you to print out and give to your customer. This isfor the customer’s records. It may also be needed at the time ofre-inspection as proof of repairs in the event of communicationproblems between the RepairNet database server, the inspectioncentre’s computer network, and the ICBC vehicle registrationdatabase.

If you wish, you can also print a copy for your own records.

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Hardcopy Repair Data FormAs a contingency in the event that you are not able to submitrepair data on RepairNet, printable forms are available for use.These forms require that you affix an official AirCare Repair Centredecal to the top right corner of the hardcopy Repair Data Form.

Obviously, you will need to print a few hardcopy Repair Data Formsto have on hand along with the official decals which can beobtained from PVTT at a cost of $50 per sheet of 10 decals. Youcan order decals from PVTT (call 604-453-5152).

Important: the hardcopy Repair Data Form is only intended to beused as a last resort when you are unable to connect to RepairNet.If you find this happening repeatedly, you should considerupgrading to a more reliable Internet service.

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Chapter 14Re-inspections

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Chapter 14 - Re-inspections

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Re-inspection ProceduresThe re-inspection procedures are the same as initial inspectionswith two exceptions:

1) If the vehicle failed the gas cap test and passed every other aspect of the initial inspection, the vehicle is not required to undergo a complete re-inspection. The motorist must take the vehicle to an inspection centre and see the inspection centre manager or assistant manager. The vehicle does not need to go into the test lanes.

2) OBD readiness requirements for re-inspections do not include the fall-back provisions of initial OBD inspections. A vehicle that has received a certified repair, and no longer has the MIL illumi-nated, but is not sufficiently ready for re-inspection, will only achieve a conditional pass. For more details on preparing a vehicle for an OBD re-inspection, see “Preparing the Vehicle For Re-inspection” on page 78.

Conditional Passes (Waivers)When a vehicle is re-inspected following diagnosis/repairs at anAirCare Certified Repair Centre, the re-inspection result can beeither a pass or a conditional pass.

A conditional pass occurs when the vehicle being re-inspected isstill not in compliance with the AirCare standards. In other words—repairs are not complete. A conditional pass can be of two types: acost waiver, or a qualified waiver.

Cost WaiverIf the technician has identified, estimated, and documented thecost of repairing the defect(s) that are still needed, the type ofconditional pass will be a cost waiver. It is referred to as a costwaiver because the reason for the conditional pass is that themotorist chose not to authorize repairs in excess of the repair costlimits.

Qualified WaiverIf the technician did not identify the emissions defect(s), aconditional pass re-inspection result is bad news and it is referredto as a qualified waiver. It means that the vehicle is still notrepaired and the technician has failed to identify the reason for theexcess emissions. This is not good.

The motorist probably won’t be happy with this result. Theyshouldn’t be happy with this result because it means that,

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although they paid for a complete emissions diagnosis, they didn’tget it. Logically, the motorist will head straight back to your shopto demand that you complete the job that they paid for.

As an AirCare technician, if you are at all concerned about yourREI, your shop’s repair record, and your quality of work, you won’tbe happy with this result either. The next chapter covers the REIand how it is affected by this and all other scenarios.

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Chapter 15Customer Complaints

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Chapter 15 - Customer Complaints

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Reasons For Customer ComplaintsComplaints occur because someone is not satisfied. In the contextof emissions repairs, a customer’s satisfaction directly relates totheir expectations.

Complaints often relate to the expected result of the work that acustomer has authorized you to do. If they authorize you todiagnose the emission defect(s) on their vehicle and to completeall of the needed repairs, the customer will expect their vehicle tobe completely repaired when you are done.

If a customer authorizes you to diagnose their vehicle but notrepair anything, they expect to get the results of your diagnosis. Ifthey authorize repairs not to exceed the cost limit, and the vehicleneeds more repairs than that, a conditional pass is a fairexpectation. Anything better than that is a bonus.

Complaints can also stem from the expected cost of repair. When acustomer receives an estimate, many customers perceive that tobe a quote. In other words—a firm price. If an estimate isperceived to be a quote, that precise amount is what the customerwill expect to pay when they come to pick up their car.

PVTT's Role In Emissions Repair ComplaintsPVTT’s certification program ensures that AirCare Certified RepairCentres are capable of performing accurate diagnostics and fairand effective repairs to failing vehicles. Ultimately, it is up to therepair centre staff to follow through with that in a fair and ethicalmanner.

However, given that PVTT recommends motorists have theirvehicles diagnosed and repaired at a shop certified by AirCare,there is an obligation for PVTT staff to mediate disputes andprovide an impartial third opinion.

The common goal for the repair centre, the customer, and PVTT isthat failing vehicles are repaired as efficiently as possible. In otherwords, as completely as possible for the least cost. PVTT will try toassist both certified technicians and the public in any way possibleto meet that common goal.

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Resolving Customer ComplaintsCustomer complaints arise when a customer is not satisfiedbecause the actual outcome of repairs did not meet theirexpectations. Therefore, the problem can be narrowed down toeither the outcome or the expectation.

Is The Complaint Justified?Comparing the actual result to the expected result is an easy wayto evaluate whether a complaint is justified. Obviously, you canonly do this if you understand what your customer’s expectation is.

The best way to ensure that you understand your customer’sexpectation is to take the time to explain and document whatrepair their vehicle needs, what the repair is going to cost, whatrepairs you will be doing, and what they should expect for a result.

If there has been miscommunication between the repair centre andthe customer concerning the cost of repairs or the performance ofthe vehicle post repair, a dissatisfied customer is almostinevitable.

Unexpected Re-inspection Result?If the customer has authorized complete repairs on the vehicle, itis expected that the vehicle will pass re-inspection. If, on the otherhand, the vehicle fails re-inspection and is conditionally passed,the motorist did not get what they paid for, and they have everyright to expect that you complete the repairs to the vehicle.

If you made an error in the repair or the diagnosis, it should beclear that the customer should not have to pay to correct yourerror. If you corrected a rich mixture and the repair uncovered aNOx problem (see “Are Other Problems Being Masked?” onpage 96), you should remind the customer that you forewarnedthem that this may occur. (You did tell them didn’t you?)

As far as getting authorization to complete any additional repairs,it will be pretty difficult to convince the customer to spend moremoney to get a result that they expected to get in the first placefor the amount they have already paid. At a minimum, it isreasonable to expect that you complete the diagnosis that hasalready been paid for and, if any of the repairs were unnecessary,you should reimburse the customer for the cost of those repairs.

Unrealistic Expectations?If a complaint stems from the customer having unrealisticexpectations, the best approach is to take the time necessary toproperly communicate with the customer and apologize for anymisunderstandings.

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Proper and effective communication of technical issues mayrequire the use of graphic or other physical examples to help thecustomer understand the situation. By far, the most useful physicalitem to support your position in a misunderstanding is a properlydocumented diagnostic result, repair estimate and work order.

If you do not have a properly documented diagnosis, estimate andwork order, you are not in a good position to reach an amiable

resolution to the complaint. This is a lose-lose situation becauseyou will probably lose a customer and the motorist’s negativeperception of your shop and of the AirCare program will probablylinger. Consequently, the complaint remains unresolved.

Unresolved Customer ComplaintsComplaints regarding repair centres that are received by PVTT aredocumented in the repair centre’s file. When a complaint isresolved you should notify PVTT with details of the resolution tothe complaint. Your file will then be updated.

All complaints should be resolved as soon as possible to minimizeany negative effects. Unresolved complaints against a repaircentre may negatively affect the shops ability to re-certify in thefuture.

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Appendix A

Engine Exchanges

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Appendix A - Engine Exchanges

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Engine Change InformationOccasionally, it may be necessary or desirable to replace theengine in a vehicle with a different engine than the one with whichit was manufactured. For vehicles manufactured for sale in Canadasince 1971, the engine and drivetrain have been designed to allowthe vehicle to conform to the applicable emission control standardsfor that year. Therefore, when replacing an engine, it is requiredthat the replacement engine also be certified as meeting the same,or more stringent, emission standards as the original engine.

Some General GuidelinesWhen replacing an engine with an engine of the same type (ie,same engine configuration, displacement, number of cylinders,and fuel system type) the replacement engine must be of the sameyear as the chassis or newer. All of the emission control devicesassociated with the original engine must also be installed or re-used from the original installation.

Emission standards differ for passenger cars, light-duty trucks andheavy-duty trucks. Installing an engine from a truck in apassenger car is generally not permitted as the emission standardsfor the truck engine are more lenient. The following table providessome useful guidelines on installing engines from different vehicletypes into other vehicles.

* The replacement calibration must be of the same model year or newer.

When installing an engine newer than the engine originallyinstalled in the vehicle, or an engine of a different type than theone originally installed, the replacement engine must be of aconfiguration certified by the original manufacturer as meeting the

Table F: Acceptability of Replacement Engines

Original Engine Calibration Replacement Engine Calibration Acceptable?

Passenger Car Passenger Car Yes *

Passenger Car Light-Duty Truck No

Passenger Car Heavy-Duty Truck No

Light-Duty Truck Passenger Car Yes*

Light-Duty Truck Light-Duty Truck Yes *

Light-Duty Truck Heavy-Duty Truck No

Heavy-Duty Truck Passenger Car Yes *

Heavy-Duty Truck Light-Duty Truck Yes *

Heavy-Duty Truck Heavy-Duty Truck Yes *

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Canadian federal emission standards of the year in which it wasbuilt. This includes all associated emission control hardwareassociated with that engine.

For vehicles from model years 1998 and later, the replacementengine must have a fully functional on-board diagnostic systemthat conforms to the OBD-II requirements for that model year.Given that the OBD system monitors components in the vehicleother than the engine (such as the evaporative emission controlsystem), installing engines in OBD-equipped vehicles that were notoriginally offered by the OEM manufacturer will not normally bepossible.

Replacing an engine with an engine that was optionally offered inthat same vehicle type in the same year is permitted, providedthat the optional engine is installed exactly as it would have beenby the manufacturer including all ancillary emission controldevices.

Installing engines that may have been available in a given chassistype in another country is only permitted if the engine wascertified as meeting an emission standard at least as stringent asthe Canadian standard for the model year of the vehicle and theengine is installed in its as-certified configuration. Generally,engines from European countries or from Japan will not be suitablefor installation in a North American vehicle.

The test of whether a particular engine exchange is acceptable iswhether the vehicle, following the engine exchange, has equivalentor lower emissions output than it had with its original engine.Conversely, engine exchanges that result in a degradation of avehicles emissions performance relative to the original engineinstallation will not be permitted.

Engine Change InformationAppendix A - Engine Exchanges

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Appendix B

Specialty Vehicle Information

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Appendix B - Specialty Vehicle Information

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About Specialty VehiclesAlthough the majority of vehicles in daily use in British Columbiaare designed and manufactured by multinational vehicle producers(i.e. those manufacturers issued World Manufacturers Identifiercodes by the Society of Automotive Engineers), there are anumber of specialty vehicle types that are also licensed to operateon BC roads.

Kit CarsA Kit Car is a vehicle constructed from a kit by an individual orsmall-volume producer. These kits typically consist of a body,interior and chassis and may resemble a vehicle that is no longerin production or a completely unique vehicle design. The kitbuilder usually supplies the engine and transmission. In BC, suchvehicles are normally registered as a "UBILT", "REPLICA",or"REPLIKIT".

Modified VehiclesA modified vehicle is a production vehicle that has been alteredfrom its original configuration to include significant powertrain,chassis and/or body modifications. In British Columbia, ICBCrequires that extensively-modified vehicles be inspected by aqualified technician to ensure that standards of safety are notcompromised by the modifications.

Some vehicles may be registered as "Modified" with a furtherdescriptor of the base vehicle. For example, a 1969 Charger thatis extensively modified and safety inspected in 2007, wouldbecome a 2007 Modified 1969 Dodge Charger. For AirCareinspection purposes, the main consideration is the year of thechassis (1969) — not the year in which the vehicle was safetyinspected (2007). Therefore, the example vehicle would be testedas a 1969 model year vehicle.

Other ClassificationsThe same general rules apply for all other specialty vehicles notclassified as "UBILT", "REPLICA" or "REPLIKIT". Regardless of thedegree of modification, vehicles are required to meet AirCarestandards for their year of manufacture.

Allowable ModificationsFor vehicles from the 1975 model year or newer, the degree towhich vehicles can be modified is limited because these vehicles

About Specialty VehiclesAppendix B - Specialty Vehicle Information

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were certified to fairly stringent exhaust emission standards andmost were equipped with catalytic converters and other emissioncontrol devices. Starting in the 1988 model year, certificationstandards became strict enough to require fuel injection andthree-way catalytic converters on almost all passenger cars andlight trucks.

Provincial regulations under the Motor Vehicle Act prohibit theremoval of any emission control devices installed by themanufacturer to comply with new vehicle standards, therefore anymodifications performed on vehicles originally equipped withemission control devices must include provisions for those devicesto be installed and to operate as designed.

As emission standards for light-duty vehicles have become morestringent over the past 30 years, the scope for modifying engineshas been reduced. That is even more the case with the advent ofon-board diagnostic systems.

California has established a certification program for aftermarketparts and accessories wherein manufacturers can demonstratethat the use of such parts does not detrimentally affect emissionsperformance. Parts that have been approved are identified withExecutive Order (EO) number and are acceptable for use onemission-controlled vehicles. Conversely, parts that result inincreased emissions are typically designated "For Off-Road UseOnly". British Columbia endorses California's program and partswith EO numbers are allowed.

About Specialty VehiclesAppendix B - Specialty Vehicle Information

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Inspection Requirements

Replicar, Replikit, Specialty, and Ubilt VehiclesAny vehicle registered as a “Replicar”, “Replikit”, “SpecialtyVehicle” or “Ubilt” on or before August 31, 1994, will be tested asthough it were a 1972 vehicle. That means it will be exempt fromthe visual inspection requirements of the AirCare inspection, andthe standards used for determining a pass or fail result on thetailpipe emission test will be those applicable to a 1972 vehicle.

Any “Replicar”, “Replikit”, “Specialty Vehicle” or “Ubilt” registeredafter August 31, 1994 will be tested as though it were a 1988model year vehicle. To pass the test, the vehicle must be fittedwith an engine and associated emission control system sufficientto comply with the Canada Motor Vehicle Safety Standard 1103,effective September 1, 1987 (0.25 grams/kilometre HC, 2.1grams/kilometre CO, and 0.6 grams/kilometre NOx). Generally,this will require the use of a closed loop fuel control system and a3-way catalytic converter. Other certified engine families andassociated hardware proven to comply with the above standard(e.g., any U.S. EPA certified engine family for model years 1981and later) may also be utilized.

Collector VehiclesInformation in this section pertains only to AirCare requirementsfor vehicles that are or will be granted Collector status by ICBC.For details of ICBC’s collector car program, visit ICBC’s website atwww.icbc.com.

When a new application is made to ICBC for Collector vehiclestatus, and the vehicle is to be licensed in rating territories D, E,or H, approval will not be granted unless the vehicle has passed arecent AirCare inspection (expiry date is not in the past). If thevehicle hasn't already passed a recent AirCare inspection when thecollector vehicle application is submitted to ICBC, the vehicleowner will be given a letter to provide to the AirCare inspectioncentre that advises them of the pending application and authorizesthem to perform an idle test on the vehicle (NOTE: thisauthorization does not apply to modified vehicles or vehicles frommodel year 1975 or newer. These vehicles must pass both theASM and the idle portions of the test). Once the vehicle haspassed the inspection, Collector plates can be issued.

Once granted Collector vehicle status, the vehicle is thereafterexempt from AirCare inspection, as long as the vehicle ownershipremains the same and the vehicle continues to be licensed with aCollector licence.

Inspection RequirementsAppendix B - Specialty Vehicle Information

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Examples

Here are a few examples showing the AirCare requirements forCollector vehicles;

EXAMPLE 1 If a vehicle already has Collector vehicle status and ownership hasnot changed . . .

. . . . an AirCare inspection is not required.

EXAMPLE 2 If a vehicle is currently licensed with regular plates, and thevehicle has passed a recent AirCare inspection (expiry date is notin the past), and the vehicle owner is now applying for Collectorvehicle status . . .

. . . . an AirCare inspection is not required.

EXAMPLE 3 If a motorist is applying for Collector status for a vehicle from amodel year older than 1975, and the vehicle will be licensed inICBC rating territories D, E, or H . . .

. . . . a passed AirCare inspection is required. ICBC will give themotorist a letter to take to the AirCare inspection centre so thevehicle can be given an idle test.

However, if the vehicle's last AirCare inspection report is still valid(expiry date is not in the past), a new AirCare inspection is notrequired.

EXAMPLE 4 If a motorist is applying for Collector status for a vehicle frommodel year 1975 or newer and the vehicle is to be licensed in ICBCRating Territories D, E, or H . . .

. . . a passed AirCare inspection is required. The vehicle mustpass both the driving (ASM) and idle portions of the test. Vehiclesfrom model year 1988 or newer must have a catalytic converter ifone was originally fitted.

However, if the vehicle's last AirCare inspection report is still valid(expiry date is not in the past), a new AirCare inspection is notrequired.

Antique Vehicles1934 and older vehicles licensed as Antique or Vintage vehicles areexempt from the AirCare program due to their limited use(parades, exhibitions, etc). For more details on licensing antiquevehicles, see ICBC’s website at www.icbc.com.

Inspection RequirementsAppendix B - Specialty Vehicle Information

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Common Issues For Specialty VehiclesVehicles that were designed prior to the introduction of emissionscontrols (1967 and older) are simpler in the sense that there isless to go wrong. Unfortunately, misconceptions about normalemission levels from older vehicles sometimes make it harder thanit needs to be for them to pass an AirCare inspection.

Are the Standards Appropriate?AirCare standards are appropriate to the technology of the vehicle.The thought that older vehicles cannot comply with AirCarestandards and run smoothly at the same time is incorrect. If anengine adjusted so that emissions are below the AirCare standardsruns rough or has poor performance — this is most likely due tothe presence of an uncorrected defect.

What may cause confusion for some is the fact that many defectscan be covered up by richening the fuel mixture. For example, avacuum leak that disrupts the air-fuel mixture going into one ormore cylinders may cause the engine to idle rough. Richening themixture may make the engine run smoother but it will also causethe CO emissions to be excessive. The solution is to repair thevacuum leak so that the engine runs smooth when the fuel mixtureis correct.

Another example of repairable defect being covered up with a“band-aid” solution is a vehicle with high HC emissions caused byintermittent misfires at idle due to poor valve sealing. Retardingthe ignition timing may reduce the HC enough to pass but willseverely harm engine performance and economy. This “detuning”is a band-aid to cover up the real problem which is the need for avalve job.

About Carburetor CalibrationOne of the most common sources of emissions problems on oldervehicles is the calibration of the carburetor(s). A carburetor isproperly calibrated when the fuel metering components such asjets and rods provide the correct amount of fuel for all of thepossible operating conditions. Worn out or mis-calibratedcarburetors will result in excess carbon monoxide (CO) emissions(too much fuel).

For any pre-emissions control vehicle, if the carburetor iscalibrated correctly, CO levels will be between .30% and 2.00%under light load conditions (such as the AirCare inspection). Acommon mistake that is made when calibrating a carburetor is toselect jets and/or metering rods that cause a relatively richmixture throughout the operating range rather than just during the

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operating conditions where a rich mixture is required for maximumperformance (acceleration and heavy load conditions). Anexcessively rich mixture throughout the operating range will notonly cause excessive CO emissions, but will also result in higherfuel consumption and reduced engine life.

What If It Can’t Pass?If a vehicle cannot pass an AirCare inspection despite the enginebeing tuned to original factory specifications (includinginternal engine specifications such as cam lift and duration,compression ratio, bore and stroke, etc.), an AirCare certifiedtechnician should review the test results with technical staff at theAirCare administration office. If your engine is running as good asit can, special standards or test instructions may apply.

SummaryThe basic combination of an internal combustion engine,carburetor(s), and ignition system has some fundamentalcharacteristics that are common to all motor vehicles, whether itbe a 1928 Model A, or a 1965 V-8 with triple carburetors. Tofunction normally, the engine needs to be mechanically sound(good compression, no vacuum leaks), the carburetor must deliverthe correct amount of fuel, and the ignition system must producesufficient spark energy in each of the engine's cylinders at theright time. When an engine, its fuel system, and its ignitionsystem are functioning normally, the emissions should be wellbelow the maximum allowable levels during an AirCare inspection.

Common Issues For Specialty VehiclesAppendix B - Specialty Vehicle Information

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Appendix C

Alternative Fueled Vehicle Information

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Appendix C - Alternative Fueled Vehicle Information

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OEM Alternative Fuel Vehicles1987 and earlier model year vehicles produced by an originalequipment manufacturer (OEM) to operate on fuels other thangasoline or diesel were not subject to federal emission standards.As a result, a certain number of propane and natural gas vehicleswere produced without emission control devices.

Every attempt has been made to incorporate the vehicleidentification numbers of these factory-built vehicles into theAirCare vehicle database, and therefore exempt them from visualinspection. However, if the VIN is not included in the database,the vehicle owner may be required to show documentation thattheir vehicle is a factory-built alternative fuel vehicle and not anaftermarket conversion if they wish to be exempt from visualinspection. These vehicles are required to meet the same tailpipeemission cutpoints as gasoline vehicles for HC and CO but not forNOx.

1988 and later model year vehicles produced by an OEM to operateon fuels other than gasoline or diesel were subject to the samefederal emission standards as gasoline fueled vehicles. Thesevehicles are required to meet the same tailpipe emission cutpointsas gasoline vehicles for HC, CO, and NOx.

OEM Alternative Fuel VehiclesAppendix C - Alternative Fueled Vehicle Information

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Conversion to Alternative Fuels

All ConversionsProduction vehicles that have been converted in the aftermarket tooperate on an alternative fuel must meet the same tailpipeemissions cutpoints as gasoline vehicles.

Model year 1998 and newer vehicles that have been converted willreceive an OBD inspection, but its results will only be advisory. Allconversions will receive a tailpipe test which will determine thepass or fail inspection result.

The general requirement for vehicles converted to operate on analternative fuel is that they cannot be degraded in terms ofemissions performance. With a few exceptions as noted below, thismeans that all factory installed emission control systems must beretained and must be functional.

Dedicated Propane or Natural GasIf a vehicle fuel system has been converted to exclusive operationon an alternative fuel, all of the original emission control systems,including an air/fuel ratio feedback system if originally fitted,should still be functional when running on that fuel except for thefollowing;

On a vehicle converted to run on a single alternative fuel, the aircleaner may be removed and replaced with a suitable alternative.However, the breather for the crankcase ventilation system mustbe configured so that blowby gases do not escape into theatmosphere when the engine is running.

On a vehicle converted to run on a single alternative fuel which isnormally held under pressure, and the gasoline tank has beenremoved from the vehicle, it is permissible to remove the gasolinetank evaporative control system, and it will not be necessary toinspect the fuel cap or filler inlet restrictor.

Dual-Fuel Propane or Natural GasFor vehicles converted to dual-fuel propane or natural gas, theheated air intake may be removed or blocked in the cold airposition, only when operating on the alternative fuel. No othermodifications to the factory-installed emissions control systemsare allowed.

All of the foregoing provisions are fully retroactive and apply toany fuel system conversion regardless of when that conversion wascarried out.

Conversion to Alternative FuelsAppendix C - Alternative Fueled Vehicle Information

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Air/Fuel Ratio Feedback Control System

Conversion before November 1, 1993

For dual-fuel vehicles still capable of running on the fuel intendedby the original manufacturer and an air/fuel ratio feedback controlsystem was originally fitted, this system should still be functionalwhen running on the original fuel, and the vehicle's emissionsshould still meet the standard to which the vehicle was originallycertified.

Conversion on or after November 1, 1993

If a vehicle was originally fitted with an air/fuel ratio feedbackcontrol system, and is still capable of running on the fuel intendedby the original manufacturer, the air/fuel ratio feedback controlsystem must still be completely functional when running on thatfuel.

Any fuel system which is added to, or replaces the original fuelsystem on a vehicle which was originally fitted with an air/fuelratio feedback control, must incorporate an air/fuel ratio feedbackcontrol system which performs a similar function to the feedbackcontrol on the original fuel system but is suitable for use as part ofthe additional or replacement fuel system.

Definitions"air/fuel ratio feedback control system" means a system whichsenses the oxygen content of the vehicle exhaust gases and usesthis information to maintain a correct air/fuel ratio.

"alternative fuel" means either a fuel other than gasoline or diesel,or, a fuel other than the one for which the vehicle was originallycertified.

Conversion to Alternative FuelsAppendix C - Alternative Fueled Vehicle Information

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Conversion to Alternative FuelsAppendix C - Alternative Fueled Vehicle Information

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Appendix D

Permissible Use Of AirCare® Mark

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Appendix D - Permissible Use Of AirCare Mark

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The AirCare LogoThe AirCare logo is a registered official mark of the Province ofBritish Columbia and can only be used with prior written consent ofthe Superintendent of Motor Vehicles through PVTT.

AirCare Certified Repair Centres are authorized to use the logo butonly in a specific fashion (see Figure 30 and Figure 31) and forspecific purposes:

• for promotional literature

• for newspaper advertisements

• for work orders

• for Yellow Pages advertisements

• to display signage advertising their status as an AirCare Certified Repair Centre but only by agreement with Pattison Sign Group (telephone 604-215-5526).

If the logo is used in any printed advertisements, the certificationnumber of the repair centre must be included in theadvertisement. If the logo is used in subscription basedadvertising, remember that it is the repair facilty’s responsibilityto ensure their AirCare certification is valid before renewingadvertising agreements. PVTT is not responsible for the validity orusefulness of any advertising.

For colour print the word “AirCare” must appear as shown in Figure30. The font used must be ITC Garamond Bold and the registeredmark symbol must follow the word "AirCare".

Figure 30: AirCare Logo Usage For Color Print

Colour Must BeBlue Pantone 072RGB = 15-35-140

Hex #003399

Colour Must BeGreen Pantone 360RGB = 96-198-89

Hex #60C659

Font can be nolarger than 1"in height.

RAirCareCertification No.

The AirCare LogoAppendix D - Permissible Use Of AirCare Mark

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For black and white print the word “AirCare” must appear as shownbelow in Figure 31. The font used must be ITC Garamond Bold andthe registered mark symbol must follow the word "AirCare".

Figure 31: AirCare Logo Usage For Black and White Print

The limited authority granted to AirCare Certified Repair Centresfor the use of the logo may be rescinded at any time and willautomatically become invalid should the repair centre cease to becertified for any reason.

PVTT, TransLink, ICBC, and the Province of British Columbiaassume no liability for damages, consequential or otherwise,related to the use of the AirCare official mark.

Font can be nolarger than 1"in height. Air ®

Certification No.

R

The AirCare LogoAppendix D - Permissible Use Of AirCare Mark

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Appendix E

AirCare Certified Repair CentreRequirements

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Appendix E- AirCare Certif ied Repair Centre Requirements

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1. BUILDING REQUIREMENTS

All AirCare Certified Repair Centres accepted by the AirCareProgram Administration Office (PAO), to participate in the AirCareProgram must be constructed and equipped so as to comply withall federal, municipal and local requirements

AirCare Certified Repair Centres must be heated as necessary tomaintain the temperature operating ranges specified for exhaustgas analyzers.

2. REFERENCE MATERIALS

Each AirCare Certified Repair Centre shall maintain an up-to-datecompilation of reference materials for passenger vehicles, trucksand motor homes subject to the AirCare program that the AirCareCertified Repair Centre normally encounters in its business. Theminimum compilation is current model year minus seven years.For example, in 2008, an AirCare Certified Repair Centre isrequired to have reference materials up to and including the 2001model year. The compilation of reference materials is not limitedto hard copy manuals but may also include electronic media.AirCare Certified Repair Centres wishing to be certified with on-lineaccess to reference materials shall provide the PAO with proof of aprepaid annual subscription for the on-line service with a minimumof 100 minutes per month.

The compilation of tune-up specifications shall as a minimuminclude;

• Tune-up Specifications & Procedures

• Computerized Engine Controls

• Fuel Systems

• Emissions Control Applications

• Vacuum/Electrical Diagrams

3. TOOLS

Each AirCare Certified Repair Technician shall have hand toolsavailable for use. If a vehicle manufacturer specifies that specialtools or testing equipment must be used to perform certain repairson certain vehicles, the AirCare Certified Repair Centre must haveavailable such equipment, whenever such repairs are beingperformed on those vehicles.

Appendix E- AirCare Certif ied Repair Centre Requirements

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4. TEST EQUIPMENT

Each AirCare Certified Repair Centre must have all the equipmentlisted below on site, operational and well maintained. The meters,gauges, etc. listed may be furnished either as separate items or ascomponents of a complete system such as an engine analyzer.

1) Oscilloscope or other ignition analyzer capable of displayingignition patterns, cylinder power contributions, sensorwaveforms and injection patterns of vehicles inspected atAirCare Certified Repair Centres.

2) Ammeter

3) Ohmmeter

4) Voltmeter

5) Tachometer

6) Vacuum/pressure gauge

7) Distributor advance tester

8) Ignition timing light or timing light with timing adjustment tosubstitute for item #7

9) Vacuum pump for applying simulated manifold vacuum toemissions control devices

10) Cam-angle/dwell meter

11) Compression test gauge

12) Exhaust emissions analyzer utilizing a gas bench andcalibration gases certified by the California Bureau ofAutomotive Repair as meeting BAR 84 or betterspecifications.

13) Scan tool and associated software for both domestic andimported vehicles to allow the extraction and interpretation ofcomputer fault codes from any vehicle being repaired that isequipped with an oxygen sensor and malfunction indicatorlight. The scan tool must also be compatible with the currentOn Board Diagnostic (OBD II) systems on 1998 and newervehicles and must include the ability to determine ReadinessMonitor status. The requirement for scan tool software interms of model year coverage is the current model yearminus seven years.

14) Computer with Internet access.

Appendix E- AirCare Certif ied Repair Centre Requirements

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15) Printer that is capable of printing copies of the RDF for theAirCare Certified Repair Centre's customers.

16) Portable handheld digital storage oscilloscope (DSO) orgraphing multi-meter capable of capturing and displayingwaveforms of sensor voltages in real time. The DSO orgraphing multi-meter must meet the following specificationsat a minimum:

• 2 channels with individual voltage range selectable for each channel

• ability to store or freeze waveforms

• time per division adjustable from 50μs to 30s (180 seconds full range)

• volts per division adjustable from 50mV to 10v (80 volts full range).

5. STAFF REQUIREMENTS

Each AirCare Certified Repair Centre must have an AirCareCertified Repair Technician on staff.

Appendix E- AirCare Certif ied Repair Centre Requirements

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Appendix E- AirCare Certif ied Repair Centre Requirements