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The AuTo Emissions Bible
How to Pass the Vehicle Emissions Test
Sam Bell Ralph Birnbaum
The Auto Emissions Bible
Copyright © 2012 by Sam Bell and Ralph Birnbaum
Cover Design, Typeset, Illustrations, and Layout: Ralph Birnbaum
NOTICE OF RIGHTSAll rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the authors.
DISCLAIMERThe information in this book is distributed on an “as is” basis, without warranty. While every pre-caution has been taken in the preparation of this book, the authors make no warranty, expressed or implied, and will not be liable for any errors or for incidental or consequential damages resulting from the use of information, herein. Users encouraged by this book to engage in repair and diag-nosis of real vehicles, do so entirely at their own volition and risk.
ISBN-13: 978-1468130188
ISBN-10: 1468130188
About the Authors
Sam Bell has owned and operated The Lusty Wrench, a premium auto repair facility in Cleveland Heights, Ohio for 32 years. In addition to the normal ebb and flow of common maintenance and repair tickets, Sam is often called upon to diagnose and repair driveability issues that stump other local repair shops.
Awards and Experience: Sam was named the 2010 Delmar/Cengage ASE Technician of the Year for earning the highest composite score on the ASE certification exams. Sam had an-other perfect score on the L1 (Advanced Engine Performance Specialist) test, and his overall scores were the highest of more than 350,000 professionals who took the tests.
Publishing Credentials: Sam is a frequent contributor to Motor magazine, and has gar-nered five International Automotive Media Awards, including a Gold Medallion. He has also won three ASBPE Awards (American Association of Business Publications Editors), including a Gold Medal. He teaches Ohio One training courses on driveability and emissions.
Ralph Birnbaum has 40 years of automotive experience, and that includes real experi-ence fixing cars as a master automotive technician, specializing in auto electric and vehicle performance issues. His is a former tech editor and editor of a national trade publication, and has been researching and preparing books and training materials for two decades.
He is currently Automotive Editor at ECS Tuning, where he prepares ad copy and training materials. He also contributes technical illustrations used in Standard Motor Products auto-motive training classes. Ralph still has all his tools, and regularly gets his hands dirty fixing real car problems.
Publishing Credentials: Writing credits include numerous automotive articles and over 20 training programs for professional technicians. His training materials have been used in both corporate and state emissions training programs.
5
Table
of Contents
6
11
29
39
61
77
93
103
135
151
157
197
219
237
261
275
281
287
293
Introduction
1 - Combustion
2 - The MIL
3 - DTCs
4- The DLC
5- Datastream
6- Monitors
7- Emission Controls
8- Testing Emissions
9 - Analyzing Test Results
10 - Troubleshooting Tips
11- Passing the Emissions Test
12 - Mode 6
13- NOx
14- Diesel Emissions
15 - Information
Glossary
OBD II Modes
Index
11
Combustion
Combustion Triangle
Oxygen and Fuel
Ignition
Suck-Squeeze-Bang-Blow
Intake Stroke - Suck
Compression Stroke - Squeeze
Power Stroke - Bang
Exhaust Stroke - Blow
A Chemical Reaction
A Balanced Mixture
Combustion By-products - Carbon Dioxide
Combustion By-products - Carbon Monoxide
Combustion By-products - Oxygen
Combustion By-products - NOx
Combustion By-products - HC
Review
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
1
19The Auto Emissions Bible
Combustion
Exhaust Stroke As the piston moves downward, the explosion burns out and its force weakens. Burned remains of the combustible charge are similar to the soot and ash left over after a wood fire goes out.
Any leftover pressure and waste gas material must be exhausted from the cylinder before a fresh charge of filtered air and fuel enters on the next intake stroke.
During the exhaust stroke, the exhaust valve opens and the next upward mo-tion of the piston blows the waste gas out of the cylin-der to the exhaust system.
This completes one entire four stroke combustion cycle. The process repeats itself as long as the elements needed for combustion continue to show up in the cylinders in the right propor-tions, at the right times.
29
The MIL 2The MIL
OBD Sensors
MIL Illumination
The MIL Matters
OBD II Scan Tool Emissions Tests
Scan Tool Tests and the MIL
MIL Tampering
MIL Fun Facts
30
31
32
33
34
35
36
37
39
DTCs
Diagnostic trouble Codes 3Sign Posts
The First Diagnostic Step
DTC Numbers
Code Number Classes
Where Do DTC Numbers Come From?
What’s In a DTC?
What Descriptors Tell Us
SAE vs. OEM DTCs
DTC Descriptor v. DTC Definition
DTC Definitions
DTC Definition Examples
One Trip-Two Trip
Freeze Frame
Putting DTCs to Work
Cautions and Pitfalls
Keep Things Simple
Exceptions to the Rule
Professional Grade Diagnostics
Review
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54-55
56
56-57
58
59
61
The DLC 4
Say AHHHHHH
Generic vs. Enhanced Data
Connect the Scan Tool
DLC Quick Tips
DLC Hiding Places
DLC BOB
Scan Tool Power
Connection Cautions
Careful There, Sparky
Texting the Vehicle
Data Protocols
Data Delivery Speed
Controller Area Network
DLC Review
62
63
64
65
66-67
68
69
70
71
72
73
74
75
76
63The Auto Emissions Bible
DLC
Scan Master
Please scroll to select scan interface:
Generic (Global) OBD IIFord EnhancedChrysler EnhancedGM EnhancedToyota EnhancedHonda Enanced
Generic Versus Enhanced Data The Generic OBD II interface provides emissions-related data to a generic scan tool interface. Generic data include DTCs and Freeze Frame, datastream, and information about monitors and their status.
An Enhanced interface provides additional data, including information about non-emissions components. Scan tools from equipment makers who make dedicated scan tools for professional repair technicians normally in-clude both generic and enhanced interfaces. Both are accessed through the DLC after the scan tool user selects the correct interface from a menu.
Dedicated scan tools are purpose-built to communicate with vehicles through multiple interfaces. Many professional grade scan tools can download and install software updates to keep them current. Our image shows a scan tool capable of communicating with several vehicle brands plus OBD II generic.
The scan tool interfaces at new car dealerships are a different story. OEM interfaces com-monly have additional, proprietary capabilities that exceed features found in aftermarket scan tools.
77
Datastream 5
Spies Everywhere!
What’s a PID?
Data Display Samples
Original OBD II Generic Datastream
Generic Data Interface
CAN Data Pids - Honda Fit
CAN Generic PIDs
The Value of Generic Datastream
Data Traps
Substituted Values
Start With Generic
Dynamic Substitution
78
79
80
81
82
83
84-85
86
87
88
89
90-91
87The Auto Emissions Bible
Datastream
Data Traps In general, scan tool interfaces connected through the OBD data link connector (DLC) allow us to sample two general classes of data: OBD II generic data, dedicated to emissions, and a separate, manu-facturer-specific data class that we’ll call en-hanced data. Enhanced datastream commonly displays additional PIDs including non-emissions items.
Core generic PIDs commonly number between 20 and 40. Manufacturer-specific PIDs displayed in the enhanced interface may number in the hundreds.
While there is some overlap in the PID lists of the two data classes, there is a big difference in the way the data are represented.
Let’s begin with the enhanced scan data display shown above. This display is typical of what you see with the “factory” interface selected on your scan tool. (There are many more PIDs than will fit on the screen.) Concentrate on the Engine Coolant Temp sensor (ECT) PIDs; there are two, and we highlight-ed them on a black background. One displays ECT voltage, and the other, an “interpretation” of that voltage, indicating coolant temperature, in degrees.
Since the normal operating range for the ECT is between zero and 5 volts, the 2.59 volt sensor value and the interpreted temperature of 189°F look logical. These readings are normal. They should be, because this car has no DTCs. It is good to go.
Now let’s see what the scan tool displays in both generic and enhanced data when there is an open in the ECT circuit. This is where we have to pay spe-cial attention to both the interface and the data, or get sidetracked.
Scan Master
Engine rpmTPS VThrottle Angle %Engine Coolant Temp VEngine Coolant TempIntake Air Temp VIntake Air TempO2 Sensor 1/1 VVehicle Speed Sensor
6400.61
02.591892.00
930.14
0
rpmV%VDegFVDegFVmph
93
Monitors 6
Monitors May Be Murky
What Is A Monitor?
Enabling Criteria
Monitors Come In Two Flavors
When Do Monitors Run?
Scheduling OBD II Tasks
Running Monitors
It’s Fixed Now. Right?
Added Thoughts
98
99
100
101
102
103
104
105
106
103
Emission
Controls 7Powertrain Management
Closed Loop
Oxygen Sensors
The AF Sensor or Wide Range Sensor (WRAF)
Catalytic Converter Chemistry
Catalyst Killers
Secondary AIR Injection
Positive Crankcase Ventilation
Evaporative Emissions
Leak Detection Simplified
Leak Detection Pumps
Natural Vacuum Leak Detection
Ford EONV
EVAP Leak Testers
Sample EVAP System Leak Test
EGR
DPFE
Linear EGR
VVT and EGR
Ignition System Designs
Common Misfire Causes
104
105
106-107
108-109
110
111
112
113
114-115
116-117
118
119
120-121
122-123
124-125
126-127
128
129
130-131
132
133
131The Auto Emissions Bible
VVT and EGR In VVT, a fluid-operated control valve rotates a cam timing mecha-nism built into the camshaft sprocket(s). Cam timing is adjusted in degrees to regulate the amount of exhaust gas that gets trapped inside the cylinder. Retarding the exhaust cam timing holds the
exhaust valves open longer, to increase valve overlap. This mixes the incom-ing air/fuel charge and trapped exhaust more completely during the intake stroke. Trapped exhaust is precisely metered, and injector pulse-width and ignition timing are modified to reduce NOx, without affecting engine performance.
Common problems include sticking cam phasers, often due to oil sludge caused by lack of basic maintenance.
Other problems include the wrong oil viscosity, low oil pressure, and electrical or hydraulic phaser solenoid failures. Even the wrong oil filter can cause the system to malfunction.
Cases of improper reassembly during a timing belt job have also resulted in numerous driveability symp-toms.
Some VVT systems change intake valve timing for better performance, and a few also control valve lift. The newest engines continually control both intake and exhaust valve timing to improve engine breathing over a wide rpm range.
Emission Controls
hydraulic control valve
camshaft
exhaustcam
sprocket
cam rotation
Cam Phaser
135
Sniff, Fix, Test
Prepare the Vehicle
Catalyst Efficiency
Lambda
Lambda and Air/Fuel Ratio Conversion
Lambda Notes
Mixture Testing Without Lambda
Catalyst Efficiency - Oxygen Efficiency Test
Catalyst Reduction Test
Catalyst Efficiency Cranking Test
Scan Tool Emissions Tests
Pass/Fail Test Standards
How Does a Vehicle Fail the Scan Tool Test?
Review
136
137
138
139
140
141
142
143
144
145
146
147
148
149
TestingEmissions 8
151
Analyzing
Test Results 9
Analyzing Test Results
Rich-Lean Analysis Using CO and O2
Interpreting Gases
Using Lambda
152
153
154
155
157
TroubleshootingTips 10
Fixing Cars
Baseline the VehicleBaseline the Vehicle
Emissions Checklist
Standard Test Procedures
Check Basic Settings
Basic Electrical System Tests
Identify the Fuel System - Air Flow
MAF Sensor Tips and Hints
Identify the Fuel System - MAP Style
MAP Sensor AS Diagnostic Tool
Backpressure Tests
The i Vac
The Importance of Oxygen Sensors
Oxygen Sensor Tips
Oxygen Sensors and Catalyst Efficiency
Using Fuel Trim for Diagnosis
Fuel Supply Tips
OBD II Vehicle Reapir Sheet
Common Repair Steps
160
161
162-163
164
165
166-167
168-169
170-171
172-173
174
175
176-177
178-179
180-184
182-182
184-185
186-187
188-189
190-195
The Auto Emissions Bible170
Troubleshooting Tips
Identify the Fuel System - MAP Style
The term Speed Density refers to PCM fuel calculations based primarily on engine speed and air density. These two factors are the primary variables, although throttle position and intake air and coolant temperatures are also monitored. Oxygen sensor feedback fine tunes these calculations in closed loop.
These are also referred to as Manifold Absolute Pressure systems since they measure manifold pressure as (a big) part of their fuel delivery calcula-tions. Manifold pressure normally increases as the throttle is opened.
MAP systems measure manifold pressure below the throttle plate. Compare this to MAF and VAF systems that measure air mass before the throttle.
MAP20 25
0
15
10
| | | | | | | | | | | | | | | | | | | | | | | | |
| | |
| |
| |
| |
| |
| | | |
| |5
Engine VacuuminHg
| | | | | | | | | | | | | | | | | 1 2 3
4567
111213
14
1098
psi
throttle
intake manifold
air intake
197
Passing the
Emissions Test 11Post-Repair Vehicle Prep
Running Monitors
Drive Cycle Special Notes
Using an OEM Drive Cycle
Practice Exercise
Monitor Exercise
Common Emissions Failures
Top Ten Emissions Failures - Oregon
Pass the Test the First Time
198-199
200
201
202
203
204-205
206
207-214
215
217
Section Two
Advanced
Troubleshooting
12 - Mode 6
13 - NOx
14 - Diesel Emissions
219
12Mode 6
What Is Mode 6?
What Does Mode 6 Look Like?
Uninterpreted - Interpreted Data
What’s Real, What Isn’t
Mode 6 Operational Overview
Mode 6 Translated
TIDs and CIDs
Interpreting a Mode 6 Minimum Test
Interpreting a Mode 6 Maximum Test
Not Too High, Not Too Low: Just Right
Mode 6 Limitations
Mode 6 - Use With Caution
Crazy Data
Crazier Data
Mode 6 Case Study
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234-235
The Auto Emissions Bible232
Mode 6
Crazy Data Lets look at sample Mode 6 data from a 1997 Lincoln Continental. This vehicle has no DTCs, the MIL is commanded OFF, and the screen capture shown below tells us that all monitors are complete. This vehicle would pass an emissions test.
Let’s erase DTCs and see what happens to Mode 6 data.
This screen is a real example of why it is important to use Mode 6 frequently, if you plan to use it at all. Experience is the best teacher.
Even though this vehicle would pass a scan tool emissions test, several Mode 6 data lines have been highlighted by the scan tool and labeled as undocumented. But there is nothing to fix. These parameters are not used in this vehicle.
The correct response is to ignore the phantom parameters.
All Monitors are complete before we erase DTCs
These data are bogus.
237
NOX 13NOx As Nemesis
Preventing NOx
Radiator Caps
Cooling Fan Codes
Cooling Systems and NOx
Testing EGR Operation
Common NOx Problem Areas
Miscellaneous NOx Tips
Where NOx Originates
Older Cars
General Tips
Tips from the Injector Guru
PCV Valves
Knock Sensors
If You Hit the Wall
238
239
240
241
242-243
244-245
246-247
248
249
250
251
252-255
256
257
258-259
261
Diesel
Emissions 1421st Century Diesels
Diesels-Old Smog, New Tricks
More Parts - More Systems - More DTCs
Diesel Monitors - Monitored Components
Diesel Fuel and Emissions
Diesel Exhaust Cleaning Components
Sample DTCs
262
263
264-267
268
269
270-271
272
The Auto Emissions Bible262
Diesel Emissions
21st Century DieselsWhen your dad was a kid, diesels were pretty simple engines, loved for their long life, low-end torque, and great fuel economy. Most diesel problems were caused by mechanical problems or poor fuel quality. Most diesel electrical system problems could be diagnosed with a test light.
No more. Diesels are 21st Century high-tech. Mechanical/hydraulic diesel injection pumps are museum pieces. The current generation of car and light truck diesels uses computer-controlled Common Rail injection.
The good news: If you already understand gas engine emissions, you’ll make the jump to diesels quickly. Common Rail injection is patterned after gas port injection, with one computer-controlled injector per cylinder. The big difference? Big pressures. Diesel high pressure fuel pumps ram fuel to the injectors though a common fuel rail. Maximum pressures now hover near 30,000 psi, in the latest generation of common rail systems. (Workers remove paint from bridge overpasses with less pressure than that!)
The injectors are different, too. Solenoid injectors are out; piezo-electric injectors are in. Piezos demand lots of watts, with some injectors operating at 150-250 volts, at amp levels that can level you if you aren’t careful. This is serious business: Wear professional safety gear, use approved voltmeters, and read the manufacturer’s safety warnings. Make sure you wear high voltage protective gloves, and put the old test light away before you hurt yourself.
Our purpose here will be to give you an overview of modern diesel compo-nents and emission strategies. OEM-specific engine and emissions strate-gies each demand a (long) book to cover exact features and specifications. But they’re out there, and the numbers are growing. Look for “clean” diesels in both light and medium duty trucks, and in passenger cars with German accents.
275
Information 15Repair Information
NASTF
iATN
Identifix
Repair Databases
276
276
277
278
279
293
Indexactual position 128
air flow style fuel system 166
AIR 24, 112, 143, 176
AllData 279
backpressure 173
BARO (barometric pressure sensor) 166
baseline vehicle 159, 192
biofuel 262
bulb check 35, 147
cam phaser 131
canister (EVAP) 114, 117, 118 124, 125
catalytic converter 110, 111, 143-145, 176, 182-183, 208, 234, 235
check engine light (see MIL)
CID 224, 225, 226,227, 228, 229
closed loop 105, 106
common rail 261
controller area network (CAN) 75, 81, 83, 84-85
CO2 (carbon dioxide) 20, 22, 27
CO (carbon monoxide) 22, 27, 142, 143, 153, 154, 161, 238
combustion 12, 20
combustion triangle 12
commanded equivalence 84, 86
commanded position 128
comprehensive component monitor (CCM) 97
compression 14
compression stroke 17
continuous monitors 97, 98
cooling fans 241
cooling systems 238-243
data protocol 73, 74
datastream 74, 78-91, 191
descriptors (DTC) 45, 47
diagnostic executive 99
diesel emissions 261-273
diesel exhaust fluid 271
diesel oxidation catalyst 270
diesel particulate filter 263, 267, 269, 271
DLC (Data Link Connector) 62-76, 64,
The Auto Emissions Bible294
Index87, 146
DLC BOB 68
DPFE (differential pressure EGR) 128
drive cycle 100, 101, 200-201, 202, 203
DTC (Diagnostic Trouble Code 30, 31, 37, 40-59, 87, 88, 89, 99, 101, 102, 121, 124, 146, 160, 190, 198, 199, 203, 206-214, 264
DTC definitions 48, 49, 94, 95
dynamic substitution 90
ECT (Engine Coolant Temperature sen-sor) 23, 45, 46, 50, 57, 79, 87, 88, 161
EGR (Exhaust Gas Recirculation) 26, 56, 126, 127, 128, 129, 161, 176, 185, 209, 244, 245, 248, 266
electrical system tests 164-165
emissions tests 136-139
emissions checklist 162
enabling criteria 97, 199, 200, 203
enhanced interface 63
EONV 120-121
EVAP (evaporative emissions) 26, 51, 56, 114, 115, 116, 119, 120, 121, 176, 211, 258
exhaust stroke 19
exhaust system leaks 24
EVAP test port 124, 125
false air 179
flow gauge 124
four stroke 14
freeze frame 52, 91, 190
FTP (fuel tank pressure sensor) 115, 116, 117
fuel supply 186-187
fuel trim 184-185
gas cap 124
GDI (gas direct injection) 187
generic interface 62, 63, 81, 82, 86, 87, 89
glow plugs 264
HC (hydrocarbons) 13, 27, 142, 143, 145, 154, 161
hybrid vehicle 55
IAC (idle air control) 115, 171
IAT (intake air temperature) 203
iATN 277
Identifix 278
ignition 14, 132-133, 162
ignition timing 160, 161, 250
inches of water 118, 119, 121
injector 16, 265
injector cleaning 252-255
intake stroke 16
internal combustion 14
interpreting gas readings 154-155
295The Auto Emissions Bible
IndexJ2534 194
keep alive memory 199, 201
knock sensor 208, 257
KOEO 35
KOER 35, 116, 164
lambda 21, 106, 108, 139-142, 143, 154-155
leak detection 116-125
leak detection pump 118
leak testers 122-125
lean mixture 24
limp home 161, 164
linear EGR 128
LTFT (long term fuel trim) 169, 184-185
MAF (mass air flow) sensor 23, 166-169, 264
manifold absolute pressure 170
MAP sensor 90, 91, 172, 264
MAP system 170-171
MIL (Malfunction Indicator Light) 30, 31, 32, 33, 34, 35, 40, 41, 51, 53, 78, 81, 101, 121, 146, 147, 152
MIL command 36, 147-148
MIL tampering 36
misfire 14, 18, 24, 176, 210
Mitchell OnDemand 279
Mode 6 220-236
monitor(s) 94-102, 98, 99, 100, 146, 198, 199, 200, 203-205, 215, 268, 269
NASTF 192, 276
natural vacuum leak detection 119
networks 55
nitrogen 13
non-continuous monitors 98
NOx 25, 27, 126, 144, 154, 238-259
OBD II 32, 33, 52, 53, 54, 64, 65, 78, 81, 82, 87, 89, 95, 152
oil viscosity 251
one-trip DTC 51
oxidation 110
oxygen (O2) 12, 13, 27, 142, 143, 153, 154
oxygen sensor (O2 sensor) 23, 56, 57, 105, 106, 107, 158, 176-183, 209, 212
oxidation 20
oxides of nitrogen (see NOx)
P0087 272
P0088 272
P0090 272
P0100-P0104 167
P0105-P0109 167
P0106-P0109 167, 272
P0108 161
The Auto Emissions Bible296
IndexP0110-P0114 167
P0112 203
P0115 23, 45, 46
P0116 45, 46
P0117 45, 46, 50
P0118 23, 45, 46, 57, 88
P0119 45, 46
P0125-P0128 23, 56, 161, 272
P0127 25
P0130-P0167 105
P0171 24, 57, 113, 115, 142, 187
P0172 - P0175 23, 113, 115, 142, 161, 187
P0174 24, 113, 115, 142
P0175 115, 142
P0190 - P0193 23, 272
P0191-P0194 187
P0234-P0249 25
P03xx 142, 256
P0300 24, 42, 210
P0325-P0335 256
P0350-P0360 161
P0400-P0406 126
P0401 56, 57, 256, 272
P0402 272
P0403 272
P0405 272
P0410 24
P0410-419 24, 112
P0420 - P0422 22, 144
P0430 - P0432 22, 144
P0441 56, 117
P0440 117
P0442 117
P0443 115, 117
P0446 56, 117
P0449 117
P0450 -P0454 117
P0455 117
P045x 115
P046C 272
P0480-P0485 25
P0505 113
P0505-P0507 256
P0560 164
P0650 148
P0671 264
P07xx, P08xx, P09xx 161
P1107 47
297The Auto Emissions Bible
IndexP2004-P2023 255
P0324-P0334 257
particulate emissions 262
PCM (Powertrain Control Module) 30, 31, 37, 41, 45, 53, 54, 78, 90, 98, 120, 121, 162, 199
PCV (Positive Crankcase Ventila-tion)113, 162, 168, 256
pending DTC 51
permanent code (permanent DTC) 32, 37, 51
PID (Parameter IDentification) 79, 83, 86, 87
piezo 265
pilot injection 265
plug-in value 88
power stroke 18
purge valve 114, 115, 116, 117, 118, 120
radiator cap 240
readiness status 147
reduction 110, 144
repair database 193, 201
repair grade analyzers 136, 137
repair sheet 188-189
reprogramming 194
SAE 44
scan tool 63, 64, 69, 70, 71, 74, 80, 87, 88,
89, 160, 220, 221
scan tool emissions test 34, 35, 36, 95, 146, 152
Schrader valve 124
secondary air injection (see AIR)
selective catalyst reduction 271
sensors 31
STFT (short term fuel trim) 184, 185
spark 14
spark-ignition 14, 17
spark plug heat range 247
speed density (see MAP system)
stoichiometry 21, 105, 106
tailpipe cooler 271
targeted gases 20
task manager 99
temperature sensors 267, 271
throttle valve 267
TID (Test ID) 224, 225, 226,227, 228, 229
two trip DTC 51
trip 98, 100
TSB (technical service bulletin) 194
trouble trees 58
U-codes 55
ULSD (ultra low sulfur diesel) 269
The Auto Emissions Bible298
vacuum (engine) 161
vacuum gauge 174-175
VAF (vane air flow sensor) 166
VECI (Vehicle Emissions Certification Information 160
vent valve (canister vent) 115, 116, 117, 118 120, 121
VIN (Vehicle Identification Number) 34, 36
VIR 158, 159
VSV (vacuum switching valve) 128
VVT (variable valve timing) 130-131
wide range air fuel sensor 108, 109
Index