diesel-to-natural gas (dng) conversion manual … dng conversion packet.pdfconversion requires...

DIESEL-TO-NATURAL GAS (DNG)

CONVERSION MANUAL

Mack E7 MY 1994 - 2006

DISCLAIMER

This manual is intended for use by qualified and experienced technical personnel with formal training in the diesel-to-natural gas engine conversion process and the operation and maintenance of heavy-duty diesel engines. This manual was neither designed nor intended as a technical guide for diesel engines and assumes a high degree of understanding of diesel engine operation and theory by the reader.

CONTACT INFORMATION

For information about Omnitek’s line of engine control systems and other products and services, please visit our website or send us an email. For questions, concerns, or technical support please contact us at:

Omnitek Engineering, Corp. 1333 Keystone Way, #101 http://www.omnitekcorp.com Vista, CA 92081 [email protected] Tel: 760-591-0089 Fax: 760-591-0880

Omnitek has endeavored to ensure the accuracy of this document. Customer feedback is very important to us. Please report any errors or submit any suggestions to Omnitek technical support.

LEGAL NOTICE

Omnitek’s ECM system is intended for use only by approved technicians trained in its theory and operation. Improper calibration or use of the system can cause unsafe conditions along with premature wear or failure of engine, vehicle, or electrical components, and may cause the installation to violate local laws or regulations. Local laws and regulations always supersede calibrations or practices recommended in Omnitek’s engine control documentation.

Disassembly, reverse compilation, or unauthorized reproduction of computer information provided with the purchase of the Omnitek ECM system constitutes a copyright violation and will be prosecuted under the authority of international treaties. This document is copyrighted ©2014 by Omnitek Engineering, Corp. Reproduction in whole or in part of this manual is strictly prohibited, except where explicitly indicated.

Omnitek reserves the right to modify the hardware and software specifications for the ECM system and components, without notice.

ONLY QUALIFIED PERSONNEL SHOULD ATTEMPT THE DIESEL-TO-NATURAL GAS ENGINE CONVERSION PROCESS.

C.10690, DNG Conversion Manual Mack E7 of 43

http://www.emissionsolutionsinc.com/

mailto:[email protected]

Table of Contents 1 BUILDING A NATURAL GAS ENGINE............................................................................................6

Primary differences between a diesel engine overhaul and diesel-to-natural gas engine conversion........6

Compatible Fuel Types..............................................................................................................................7

Motor Oil ...................................................................................................................................................7

Engine Operating Temperatures and Cooling System...............................................................................7

Very Hot Exhaust System..........................................................................................................................7

Engine Efficiency ......................................................................................................................................7

Emissions...................................................................................................................................................8

Engine and DNG Kit Warranty .................................................................................................................8

Commissioning ..........................................................................................................................................8

Final Programming of the ECU .................................................................................................................8

2 DESCRIPTION OF COMPONENTS....................................................................................................9

Injector Manifold/CNG Mixing Ring ........................................................................................................9

CNG Mixing Ring .....................................................................................................................................9

CNG Injector High-Flow...........................................................................................................................9

Engine Coolant Temperature Sensor (ECTS)..........................................................................................10

Intake Air Temperature Sensor (IATS) ...................................................................................................10

Combined CNG Fuel Pressure and Temperature Sensor (PTS) ..............................................................10

Exhaust Gas Temperature Sensor ............................................................................................................10

Universal Exhaust Gas Oxygen Sensor (UEGO).....................................................................................10

Heated Exhaust Gas Oxygen Sensor (HEGO) 4-wire .............................................................................10

Boost Pressure Sensor..............................................................................................................................11

Manifold Absolute Pressure Sensor (MAP) ............................................................................................11

CNG Filter ...............................................................................................................................................11

Turbo charger...........................................................................................................................................11

High Energy Ignition Coil .......................................................................................................................11

Catalytic Converter ..................................................................................................................................12

Critical Compression Ratio (CCR) & NG Pistons...................................................................................12

Spark Plugs and Spark Plug Wires for NG Engines ................................................................................12

Piston Rings .............................................................................................................................................12

Valves, Valve Seats and Guides ..............................................................................................................13

OmniWatch Software ..............................................................................................................................13


3 GENERAL SAFETY PRECAUTIONS...............................................................................................14

Before Beginning Installation Procedure.................................................................................................14

Natural Gas Vehicle Fuel System Standards ...........................................................................................14

Fire or Explosion Hazards .......................................................................................................................14

Venting CNG Fuel ...................................................................................................................................15

CNG Fuel Tank Safety ............................................................................................................................15

Visual Inspection .....................................................................................................................................15

Painting a CNG Vehicle ..........................................................................................................................16

Tanks Involved in Accidents ...................................................................................................................16

Pressure Relief Device.............................................................................................................................16

Fuel System Modifications ......................................................................................................................16

Health Hazards.........................................................................................................................................16

4 INSTALLATION PREPARATION ....................................................................................................17

Special Tools ...........................................................................................................................................17

CNG Gas Composition ............................................................................................................................18

CNG Storage and Supply Systems ..........................................................................................................18

5 INSTALLATION PROCEDURES......................................................................................................20

5.1 Removal of Old Components ............................................................................................................20

5.2 Cylinder Head Modifications for Spark Plugs...................................................................................20

5.3 Valves ................................................................................................................................................21

5.4 Pistons and Piston Rings....................................................................................................................21

5.5 Ignition Coils .....................................................................................................................................23

5.6 Sensors...............................................................................................................................................23

5.7 Catalytic Converter ............................................................................................................................25

5.8 Air/Fuel Module ................................................................................................................................26

5.9 Turbo Modifications ..........................................................................................................................27

5.10 CNG Regulator Mounting ...............................................................................................................27

5.11 Wastegate Solenoid..........................................................................................................................29

5.12 Wiring Harness ................................................................................................................................30

5.13 ECM.................................................................................................................................................32

6 SCHEMATICS ....................................................................................................................................34

6.1 DNG Component Locations ..............................................................................................................34

6.2 Ring Gap Clearances .........................................................................................................................35


6.3 Vacuum Hose Routing.......................................................................................................................35

6.4 Wiring Schematic ..............................................................................................................................36

6.5 J1939 Connectors Diagram................................................................................................................37

6.6 Removing and Installing Spark Plugs................................................................................................38

6.7 Spark Plug Failure Modes..................................................................................................................39

6.8 Oxygen Sensor Failure Modes...........................................................................................................40

7 REFERENCES.....................................................................................................................................41

Unit Conversions..................................................................................................................................41

Metric Prefixes .....................................................................................................................................41

Torque Specification ............................................................................................................................42

Automotive Acronyms .........................................................................................................................42

8 ENGINE CHECK LIST.......................................................................................................................43


1 BUILDING A NATURAL GAS ENGINE

Building a natural gas engine is significantly different than building a diesel engine. Converting a diesel engine to operate on natural gas requires technical expertise to perform engine modifications.

ATTENTION:

EXCEPT FOR PROCEDURES SPECIFIC TO A DIESEL-TO-NATURAL GAS ENGINE CONVERSION AS OUTLINED IN THIS MANUAL, THE

PROCEDURE AND SPECIFICATIONS OUTLINED IN THIS WORKSHOP MANUAL ILLUSTRATING AND INSTRUCTING ON HOW TO OVERHAUL THE MACK E7 ENGINES MUST BE FOLLOWED.

Primary differences between a diesel engine overhaul and diesel-to-natural gas engine conversion

Wear Tolerances: Same.

Pistons: Natural gas uses low-compression pistons.

> New low-compression pistons are supplied.

Valves and Valve Seats: Natural gas uses high-temperature Inconel valves and Stellite 12 valve seats.

> New valves and seats are supplied.

Injectors: Diesel injectors are removed and replaced by spark plugs.

Cylinder Head: The cylinder head is modified so spark plugs can be installed.

> Spark plug adapters are supplied.

ECM: The OE ECM is removed and various new sensors, gas injectors, ignition coils and the Omnitek Engine Control Module are installed

Catalytic Converter: A 3-way Catalytic Converter is installed.

Label: A Supplemental Emissions Label is attached to the engine.

The Diesel-to-Natural Gas Engine Conversion Technology (DNG) is a retrofit technology that can be used to convert a diesel engine to a natural gas engine. This is achieved through the application of proprietary and patented technologies. Conversion requires permanent modifications of the engine. After conversion, the engine will operate on 100% natural gas.

The system utilizes electronically controlled fuel injectors and a catalytic converter to assure performance and emission compliance.


Compatible Fuel Types

The natural gas System is compatible with methane-based fuels such as Compressed Natural Gas (CNG), Liquid Natural Gas (LNG) and Biogas.

Motor Oil

Modern petroleum based motor oils have greatly improved. It is not uncommon for conventional engines to go 10,000 miles between oil change intervals. The biggest problem is not that the oil wears out, but that it becomes contaminated with combustion by-products, which then form acids, varnishes, and other damaging solvents. A dedicated natural gas engine does not produce these oil contaminations and can extend oil change intervals.

Natural gas engines require lube oil specifically formulated for natural gas operation. Natural gas burns with minimum particulate residues so engine oil is kept cleaner during engine operation. No changes should be made to the OEM’s recommended service intervals without complete engine oil and wear analysis and consultation with the OEM.

WARNING Motor oil specially formulated for natural gas engines must be used. If diesel motor oil is used, accelerated wear will occur.

Engine Operating Temperatures and Cooling System

Engine heat rejection rates while operating in natural gas mode are slightly higher. The design of the DNG Kit assures engine exhaust gas temperature, coolant temperature, oil temperature and manifold air temperature levels remain within acceptable limits.

The engine must never be operated without a cooling system thermostat. If the engine is not allowed to reach normal operating temperature the ECU will always remain in the cold-start mode and the engine will run too rich.

Engine must have thermostat installed at all times and engine must be able to reach an operating temperature >85 C.

WARNING The coolant system must be filled with Antifreeze. Never operate engine with pure water in the cooling system.

Very Hot Exhaust System

WARNING In a natural gas engine, the turbo and exhaust manifold get much hotter during operation than typical diesel engines. Therefore any components susceptible to high heat, such as hoses wires, cowlings, covers, or other plastic components can melt and/or catch fire. To prevent this, a heat shield should be installed between the exhaust manifold/turbo and nearby components.

Engine Efficiency

Natural gas engine efficiency is reduced by 10% to 15% from diesel operation.


Emissions

The DNG Kit was designed to comply with all applicable emission standards and comes equipped with a 3-way catalytic converter. Immediately shut off the engine if a misfire develops. An engine misfire condition will severely damage the catalytic converter.

Engine and DNG Kit Warranty

Warranty obligation is transferred from the OE Diesel Engine Manufacturer to Omnitek Engineering Corp. Please reference the most current Omnitek Limited Product Warranty Policy for details. The warranty gives you specific legal rights, and you may also have other rights which vary from state to state / country to country.

Commissioning

Prior to commissioning of the vehicle in natural gas mode, a thorough inspection of the engine and vehicle should be performed. This check should include all major systems and components (cooling, lubrication, fuel, charge air cooling, air intake, drive-train, sensors, etc.) for proper operation and condition.

All outstanding maintenance and/or performance issues with the engine and/or vehicle should be addressed prior to running of the engine in natural gas mode.

Omnitek relies on the experience of the installation technician to determine if a particular diesel engine is fit for conversion to natural gas. If in doubt, please note any discrepancies with the engine and/or vehicle and contact Omnitek for technical guidance.

Final Programming of the ECU

Final programming of the ECU will be performed by Omnitek over the internet. This will assure that only Omnitek has access to calibration files.

All technicians performing conversions, as well as service personnel, will be supplied am Access Code, Level 2 to the OmniWatch Software, which only allows engine monitoring, resetting of maintenance reminders, and DTC clearing. Please read the “OmniWatch Manual” for guidelines on using this software.

Note:

Prior to starting the DNG Engine installation process, confirm that all components appear to be in good condition and are in working order.


2 DESCRIPTION OF COMPONENTS

Below are descriptions of the components needed for Omnitek’s diesel to natural gas conversion. For a detailed list of all components with part numbers and quantities, see attached PDF document titled “Mack E7 Parts Catalog.”

Injector Manifold/CNG Mixing Ring

Since the ECM system delivers natural gas in pulses rather than continuously, the patented Mixing Ring is critical to proper air / gas mixing. The Mixing Ring used by the ECM system is not a self-metering Venturi. Instead, the gas quantity metering is done by the ECM by varying injector opening times. This allows higher-pressure gas delivery into the air stream, which results in better mixing. Also, the Mixing Ring does not create a power-robbing air restriction. The Mixing Ring is part of the Injectors/Throttle Assembly for preassembled units.

CNG Mixing Ring

The Mixing Ring is custom-engineered for the engine. Its function is to ensure that the natural gas is properly mixed with incoming air, and that an equal amount of natural gas is delivered to each cylinder. Because the ECM system delivers natural gas in pulses rather than continuously, the design and proper installation of the Mixing Ring is critical to proper air / gas mixing. The tabs on the Mixing Ring ensure proper installation.

Improper installation of the Mixing Ring, or installation of a mixing device not designed for the specific application may cause the following operational problems:

Rough idle or unwillingness to idle at all Poor exhaust emissions MIL Lamp illumination (setting of diagnostic codes) High fuel consumption Damage to catalytic converter Engine damage due to one or more lean cylinders Low engine power Oxygen Sensor “Inversion”

CNG Injector High-Flow

The Omnitek gas injector is designed for precise metering of gaseous hydrocarbon-based fuels with the automotive industry as its primary market.


CNG Regulator

The ECM and injectors require that the pressure before the injectors be constant, despite changing gas and ambient air temperatures and cylinder pressures. The primary function of the regulator is to supply gas at a predetermined and constant pressure to the injectors. This set pressure depends on the application, but usually ranges from 45-100psi.

Engine Coolant Temperature Sensor (ECTS)

The The Engine Coolant Temperature Sensor (ECTS), measures engine coolant temperature. It is installed on the engine block during the conversion process.

Intake Air Temperature Sensor (IATS)

The Intake Air Temperature sensor is used in conjunction with the ECTS and the Manifold Absolute Pressure sensor for calculating the mass of air drawn into the engine each cycle. It is installed on the Air/Fuel Module during the conversion process.

Combined CNG Fuel Pressure and Temperature Sensor (PTS)

The CNG Fuel Pressure and Temperature Sensor senses the pressure and temperature of the CNG immediately before the injectors.

Exhaust Gas Temperature Sensor

The Exhaust Gas Temperature Sensor is installed in the exhaust system right at the turbo outlet and near the pre-converter oxygen sensor. It is used primarily for safety, but also for rich-burn/lean-burn tuning.

Universal Exhaust Gas Oxygen Sensor (UEGO)

The UEGO Sensor, also known as a wideband oxygen sensor, is installed in the exhaust system before the catalytic converter.

Heated Exhaust Gas Oxygen Sensor (HEGO) 4-wire

The HEGO Sensor is installed post catalyst and measures the presence of oxygen after the catalytic converter. This ensures maximum performance of the catalyst at all times and can help ensure good emissions over the life of the vehicle as the catalyst possibly degrades over time. It works in concert with the front oxygen sensor (UEGO) to adjust fuel delivery keeping exhaust emissions as low as possible.


Boost Pressure Sensor

The Boost Pressure Sensor measures boost pressure before the throttle and is used in conjunction with the Manifold Absolute Air Pressure. The system uses a 3 bar sensor and is located on the Air/Fuel Module.

Manifold Absolute Pressure Sensor (MAP)

The Manifold Absolute Pressure Sensor (MAP) is located after the throttle. The system uses a 3 bar sensor and is located on the Air/Fuel Module.

CNG Filter

GNG engines need protection from solid particulate matter and oil aerosols, both of which can damage fuel injectors, carburetors, and regulators. By combining both forms of filtration in one element, the CNG175 filter provides highly efficient and cost effective fuel system protection. This filter should only be installed by a qualified technician.

Turbo charger

The turbocharger boosts the efficiency of the engine while running on compressed natural gas. When converting to DNG, use only Omnitek supplied or modified turbo for optimal boost control. In a natural gas engine, the turbo and exhaust manifold get much hotter during operation than typical diesel engines. Therefore any components susceptible to high heat, such as hoses wires, cowlings, covers, or other plastic components can melt and/or catch fire. To prevent this, a heat shield should be installed between the turbo and nearby components.

Wastegate Actuator Solenoid & Wastegate Actuator

The Wastegate Actuator Solenoid is controlled by the ECM and opens the Wastegate on command, controlling the boost generated by the engine.

The Wastegate Actuator opens the wastegate, allowing excess boost to exit via the exhaust system.

High Energy Ignition Coil

The High Energy Ignition Coil stores the ignition energy and produces the high voltages required to generate a spark when the ignition is triggered.


Catalytic Converter

The system utilizes a catalytic converter to assure performance and emission compliance. The converter must operate at a high temperature to reduce emissions; therefore the converter is installed approximately 3 feet to 4 feet after the turbocharger. Installing the converter further away from the turbocharger will significantly effect emissions and is not allowed.

Critical Compression Ratio (CCR) & NG Pistons

The Critical Compression Ratio is EXTREMELY important. As the piston moves up during its compression stroke, the A/F mixture temperature increases. At a critical pressure, the temperature reaches the point where the mixture will spontaneously ignite. The increased octane of NG and inherently high auto-ignition temperature, allow a higher compression ratio than with gasoline. Increased compression improves the engine’s efficiency. Natural Gas has a CCR of around 16.5, depending on the purity of the fuel. For this reason, low-compression pistons are supplied with the DNG Kit.

Spark Plugs and Spark Plug Wires for NG Engines

Reducing the spark plug gap reduces the ignition demand and adds to plug life. The spark plug electrode gap should be 0.013" to 0.015” (.35mm to .40mm). Since spark voltage and engine temperature demands of natural gas engines are higher, high quality spark plug

ds to plug life. es are advantageous.

Omnitek premium spark plugs with precious metal electrodes should be used.

wires must be used in combination with the long-life spark plugs.

Reducing the spark plug gap reduces the ignition demand and ad Spark plugs with multiple ground electrod Spark plugs should be a cold heat range. For extended service intervals and to keep spark plug wear to a minimum,

Piston Rings

For minimal leak-down and reduced oil consumption, reduced-cross

clearance a

s engines. For this application, the 3-piece oil ring design is farsuperior.

section

nd gap.

piston rings are supplied, as well as 3-piece oil rings.

Accuracy of piston assembly is very important, as is ringFollow the OE piston ring installation procedure carefully.

Oil rings used in un-throttled diesel engines are of the 2-piece design. This design is not optimum in high engine vacuum applications such as in throttled natural ga


Valves, Valve Seats and Guides

The supplied valves, valve seats and valve guides are made out of high-temperature materials specifically designed for use with natural gas.

Dimensional specifications and installation procedures are the same as for the OE diesel parts, except for the valve seat angles. The intake valve seat angle is set at 20° and the exhaust seat angle is set at 30°. This will greatly increase durability and extend the valve adjustment frequency.

For adequate lubrication and to prevent excessive oil consumption, high quality valve guide seals are also supplied. Correctly adjusted valves are very important for the engine to work satisfactorily. If the valves are not adjusted to specification, the air/fuel mixture intake in the cylinders will be insufficient to generate good engine power and assure easy starting of the engine.

OmniWatch Software

The OmniWatch software is a proprietary Windows-based PC program used for calibration and diagnostic work on the ECM system. Using a Datalink adapter in conjunction with this program allows the user to get real time information from the Engine Control Module (ECM).

OmniWatch has the ability to log these values to a spreadsheet which allows the user to record data while the vehicle is in use and analyze it later. This tool is particularly valuable when troubleshooting intermittent problems allowing the user to catch the problem in the act. OmnWatch can read Diagnostic Trouble Codes (DTCs) from the ECM to record problems which occur during vehicle operation.

The program also allows the user to change both the vehicle calibration and firmware files in the ECM, a function which is required when installing the ECM system on multiple engine configurations and which allows the user to update the operation code if revisions become available after installing an ECM system.


3 GENERAL SAFETY PRECAUTIONS

WARNING Deviation from these installation instructions and technical guidelines may lead to improper operation of the engine and natural gas system and/or personal injury or death to operators and nearby personnel.

Before Beginning Installation Procedure

Ensure that the work area has adequate ventilation in order to prevent accumulation of gas caused by undetected leaks. Accumulations of natural gas or other hydrocarbon vapors can result in high-energy explosions that can damage or destroy structures and cause injury or death to nearby personnel.

Keep an appropriately rated fire extinguisher in a readily accessible location during all phases of installation.

Observe all warnings found on the equipment. Ensure that warning labels are easily legible and not obstructed by dirt, grease or other equipment.

Do not install any component that appears to have been tampered with, subjected to high temperatures, or damaged in any way. Installation of a damaged component may result in gas leaks and/or improper operation of the natural gas system.

Do not attempt to operate engine or vehicle until a thorough leak check has been completed. Use of an industry standard leak detection fluid (such as “Snoop”) is required on all gas connections, joints and flanges. ALL LEAKS MUST BE FIXED PRIOR TO OPERATING ENGINE IN NATURAL GAS MODE.

All natural gas system components must be used within the temperature and pressure ranges specified in this manual or as otherwise dictated by component labeling. Operation of components outside of design temperature and pressure limits can result in fire, explosion and/or harm to personnel.

Natural Gas Vehicle Fuel System Standards

The National Fire Protection Association (NFPA) has specified a Technical Standard for the design and building of CNG fuel systems. Visit http://www.nfpa.org/ for more information.

Fire or Explosion Hazards

Do not park or service a CNG fueled vehicle near any source of fire such as: open flame, cigarettes or smoking materials, sparks, excessive heat, welding, or body grinding equipment.

Avoid parking the vehicle near electrical equipment that discharges sparks through normal operation, for example, motors, electrical switches, and radio transmission equipment.

Vent the CNG system using the recommended service procedures before storing a CNG vehicle indoors.

Avoid servicing a CNG vehicle with a natural gas leak indoors. Determine the source of the leak, vent the fuel system as necessary then repair the natural gas leak. If any source of fire or ignition contacts natural gas, a fire could result. If the fuel is confined and ignited in an enclosed, unventilated area, an explosion could result.

Be alert for the odor of natural gas. natural gas is normally colorless and odorless. As a safety measure, a scent (Ethyl Mercaptan) is added to aid detection of fuel leaks.


http://www.nfpa.org/

Do not smoke or carry lighted tobacco when servicing or handling CNG fuel system components. Store natural gas fueled vehicles and components away from heat, fire and any source of sparks. Because natural gas is lighter than air, accidentally released gas will accumulate near the ceiling of a

building.

Venting CNG Fuel

Natural gas can be vented (discharged) into the atmosphere. However, when performing this procedure, the steps described in the following warning must be observed.

Always vent CNG tanks in a well-ventilated area that is approved and equipped for these procedures.

Always use approved venting tools and procedures as described in the service manual. Extinguish all smoking materials before beginning venting procedure. Never vent near open flame, heat sources, and sparks. Never discharge gas by opening the tank valves. High pressure expulsion can cause serious

injury. Always ground the vehicle and natural gas system. High pressure discharge can cause static

electricity buildup and subsequent sparking. Venting of fuel tanks requires the use of a vent stack that is approved and equipped for the

procedure. Follow all local regulations and consult your local fire and environmental authorities for specific regulations.

Use only electrically conductive sealant on natural gas lines. Never use conventional Teflon tape or pipe sealant.

CNG Fuel Tank Safety

The tanks must be rated for use at 3600 psi.

WARNING Never over-pressurize the tanks.

If damage to the tank is observed during maintenance/repair, the tank must be inspected and approved by qualified personnel. If the tank is rejected, the tank must be replaced before the vehicle is returned to service.

To maintain compliance with federal regulations, the tank must be visually inspected every 36 months or 36,000 miles (58,000 km), whichever comes first.

The service life of a CNG fuel tank is listed on the tank’s label. If the tank label is missing or unreadable, the tank must be replaced.

A tank that does not pass the inspection criteria must be replaced before the vehicle is returned to service using natural gas.

Visual Inspection

Only qualified personnel in accordance with the manufacturer’s established inspection criteria and the procedures outlined by the Compressed Gas Association (CGA) must perform visual inspection for external damage and deterioration.

A technician that finds tank damage and/or deterioration must note this on the repair order. This damage must be communicated to the customer prior to releasing the vehicle.

Levels of tank damage determine whether the damaged tank can be repaired or must be replaced. These levels of damage will be explained later in this section.


Painting a CNG Vehicle

If a CNG vehicle requires painting, and the vehicle will be placed in a paint oven, the CNG tank must be vented (emptied of fuel). This is done to prevent an overpressure condition during a soak in the paint oven.

WARNING Failure to completely empty the fuel tank prior to the vehicle being placed in a paint oven can create a fire and explosion hazard.

Tanks Involved in Accidents

CNG vehicles that have been involved in an accident must have the fuel tank inspected and approved by qualified personnel before being returned to service.

WARNING Tanks that have been subject to fire must be condemned and removed from service.

Pressure Relief Device

All CNG tank valves have a lead insert inside that will melt if the tank is exposed to temperatures in excess of 100 °C (212 °F). This will allow the pressure inside the tank to be relieved, in the event that the tank is exposed to excessive heat or a fire. Most CNG vehicles have electrically actuated solenoid tank valves. These are normally closed valves that are actuated when the ignition key is turned on.

Fuel System Modifications

Do not modify the fuel system or components, or replace components with parts that don’t meet specifications.

The particular system installed on a vehicle is precisely calibrated for efficient operation. The use of different components or materials could produce an untested configuration that could result in fire, explosion, and personal injury or cause engine damage from incorrect fuel metering.

Health Hazards

Avoid inhaling natural gas or occupying confined areas containing natural gas. In large quantities, natural gas can displace enough oxygen to make the surrounding air unfit to

breathe and possibly cause asphyxiation. If a person breathes natural gas or air lacking oxygen due to the presence of natural gas,

headache, dizziness, and weakness in the extremities can result. In the event of asphyxiation from inhaling natural gas, move the victim immediately to fresh air

and contact a physician or medical emergency personnel for artificial respiration or other required treatment.

If the odor of natural gas is present at any time, warn all persons in the area to extinguish all flames and tobacco products. Shut off electrical and air power equipment and evacuate the area immediately. Ventilate the area until the odor of gas is no longer present.


4 INSTALLATION PREPARATION

Omnitek supplies as complete a system as is practical without limiting application flexibility. However, because of variation between engines and vehicles, fabrication of miscellaneous brackets, braces and shields is usually necessary. A skilled mechanic familiar with electronic engine controls and natural gas systems will have no trouble with installation of the ECM system. Be prepared and make sure materials and equipment are on hand.

A clean engine and vehicle makes installation much easier and faster. Wash the engine thoroughly. Make sure you have all necessary tools and materials available and ensure that fire extinguishers are available

ty precautions are taken. and appropriate safe

Vehicle Condition The ECM system will not function properly on a vehicle which has not been properly maintained. The vehicle must be in good working order. This includes the following:

Charging System: The alternator, drive belts, battery, power and ground cables, as well as wiring and connectors must all be working properly. Voltage surges during power-up and power-down may cause the following symptoms:

Vehicle and engine statistics loss Poor engine performance and emissions Permanent damage to ECM electronic components, and Diagnostic trouble code loss

Engine: The engine must be in good working order. Any loss of compression or excess bypass of oil and crankcase emissions into the air intake or combustion chambers can cause the following:

Low engine performance and poor emissions Damage to the Oxygen Sensor Damage to the Catalytic Converter

Exhaust System: Any leaks in the exhaust system before the Oxygen Sensor will cause poor engine performance and emissions.

Special Tools

In addition to a standard selection of both metric and imperial wrenches and sockets, screwdrivers and other common automotive shop tools, the following are less common tools which may be required for installation:

If your system uses screw-in injectors, a narrow 17mm or 11/16” wrench will be required. It must have a profile of 4mm or less.

Oetiker clamp pincers are used for crimping the clamp on the PRV hose. Contact Omnitek for proper tool specification.

NPTF taps and drills may be required for installation of some sensors and the mixing device. Some wire harness assembly may be required in which electrical terminal crimpers may be needed.


CNG Gas Composition

As with any other engine and engine management system, proper fuel quality and composition are vital to correct operation of the engine. The following outlines some basic requirements for CNG quality and composition. For more detailed requirements see SAE J1616 Recommended Practice for Compressed Natural Gas Vehicle Fuel.

Moisture Content: The local dew point temperature of the fuel should be 41-43°F below the monthly lowest air temperature of the area in which the vehicle will be operating.

Particulate and Foreign Material: CNG fuel delivered to the vehicle should have particulate matter content equal to or less than 5µm in size.

Oil Content: Excessively high levels of lubricating oil entrained or absorbed in natural gas can condense and may create vehicle operational problems, e.g. liquids in the fuel pressure regulator and fouled injectors. Precise levels of oil which are acceptable in the fuel supply cannot be specified as they are determined by several factors which may vary between vehicles and engines. However, it must be understood that levels adversely affecting NGV performance are unacceptable by definition. Lubricated compressor oil levels should be monitored, and coalescing filters may be installed downstream of the compressor discharge to control oil.

Natural Gas Odorant: Natural gas introduced into any CNG fueling station or vehicle shall have a distinctive odor potent enough for its presence to be detected at a concentration well below its lower flammability limit.

Chemical Composition: The chemical makeup of the fuel is complex. See SAE J1616 for more information on the required chemical composition of CNG for vehicles.

CNG Storage and Supply Systems

Typical installation of a CNG system begins with installation of the CNG storage cylinders. Installation of the high-pressure storage system is beyond the scope of this manual. Know the codes and standards in your jurisdiction and follow them. Supplement that with a thorough knowledge of CNG safety. The Natural Gas Coalition provides documents on this topic. For more information, visit their website at: http://www.ngvc.org

To ensure proper and reliable operation of the ECM system the installer must ensure the following:

CNG supply to the ECM system must be clean and dry. In most cases a coalescing filter is required to remove trace amounts of compressor oil and other contaminants. Even if the CNG supply from the fill station is reliably clean, small particles of rust and other debris can form inside storage cylinders and fittings. Type and size of coalescing filters depend heavily on CNG supply purity. Experimentation may be required to determine the proper filter for your location and vehicle. Omnitek can assist you in selecting a coalescing filter for your application, please contact customer service for support.

CAUTION Failure to ensure that the CNG supply to the ECM system is clean and dry at all times may degrade the performance of system components such as regulators and injectors. Over time vehicle performance and durability will be impaired. Problems caused by CNG contamination of ECM or engine components will not be covered under warranty.


http://www.ngvc.org/

A quick-action, quarter turn, high-pressure shut-off valve should be installed in the engine compartment. The function of this valve is to isolate the engine and ECM system from high pressure CNG during engine servicing or maintenance. This is an important safety feature should a leak develop while the engine is being worked on.

The tubing must be large enough to ensure unrestricted fuel flow, even at high power demands and low cylinder pressures. This will depend on the length of tubing between the cylinders and the regulator as well as engine power and regulator set-point.


5 INSTALLATION PROCEDURES

Omnitek supplies as complete a system as is practical without limiting application flexibility. However, because of variation between engines and vehicles, fabrication of miscellaneous brackets, braces and shields is usually necessary. A skilled mechanic familiar with electronic engine controls and natural gas systems will have no trouble with installation of the ECM system. Be prepared and make sure materials and equipment are on hand. For an overall view of all newly installed component locations, see Schematic 6.1.

5.1 Removal of Old Components

Remove all components in the system associated with the injectors, fuel line, and some oil supply components. Plug all unused ports.

Remove the Fuel pump and replace with a plate as shown.

Remove all components associated with the EGR system (the cooler, connecting pipes, bolts, VGR actuator and EGR position sensor) and discard.

The six electronic pumps used for the fuel system will no longer be needed after the conversion. Remove them and replace them with the Unit Injector Blockoff and Injector Blockoff Caps.

5.2 Cylinder Head Modifications for Spark Plugs

The cylinder head must be modified to allow for the installation of spark plugs. Generally, the spark plugs are installed at the same location as the diesel injectors, and some important modifications must be made.

Detailed instructions on how to modify the cylinder heads are located in the attached PDF document titled “C.10612 Mack E7 Cylinder Head Modifications.” In this document you will also see instructions for Spark Plug installation, and valve cover modifications.


5.3 Valves

New valves, valve seals, valve seats, and valve guides are provided. Dimensional specifications and installation procedures are the same as for the OE diesel parts, except for the valve seat angles. The intake valve seat angle is set at 20° and the exhaust seat angle is set at 30°. This will greatly increase durability and extend the valve adjustment frequency. For adequate lubrication and to prevent excessive oil consumption, high quality valve guide seals are also supplied.

Correctly adjusted valves are very important for the engine to work satisfactorily. If the valves are not adjusted to specification, the air/fuel mixture intake in the cylinders will be insufficient to generate good engine power and assure easy starting of the engine.

Valve Clearance Intake/Exhaust 0.635mm (0.025in)

5.4 Pistons and Piston Rings

WARNING Do not use diesel pistons when converting a diesel engine to a natural gas engine. Severe and possibly irreparable engine damage will result.

WARNING Correct orientation and sequence of ring installation, as well as ring gap orientation are very important. Incorrect installation will cause excessive blow-by and oil consumption and will result in engine smoking during operation or engine failure.

For minimal leak-down and reduced oil consumption, reduced-cross section piston rings are supplied, as well as 3-piece oil rings. Accuracy of piston assembly is very important, as is ring clearance and gap. See Schematic 6.2 for Ring Gap Clearances.

Ring gaps are often a confusing and misunderstood part of a re-ring job. There are minimum and maximum ring gap specifications, which must be observed for the best performance of a new ring set.


Minimum gap tolerances must be observed in order to prevent the ring ends from butting together as the ring expands when the engine approaches operating temperature.

SAE Recommended Automotive Compression Ring Gap Clearance

Ring Diameter End Clearance Inspection Limit

3.5425 - 4.3299 .012 - .022

4.3300 - 5.1174 .014 - .026

5.1175 - 5.9049 .016 - .030

5.9050 - 6.8899 .020 - .035

Maximum ring gap is an important part of ring performance in that too much gap results in lost compression, power loss and ultimately poor oil control. The following chart indicates the specifications for compression ring gap as outlined by the SAE (Society of Automotive Engineers) as standards for the automotive piston ring manufacturers.

NOTE When installing piston rings, always use a ring spreader. Do not attempt to spread rings for installation by hand.

Installation Procedure:

1. Remove old pistons and liners according to OEM specifications. 2. Inspect connecting rods. If damaged, recondition or replace before installing new Omnitek piston

heads. 3. Install new Omnitek sleeves into cylinders. 4. Clean cylinder walls of dirt and debris using hot water and mild soap. Dry the liner. 5. Immediately after cleaning, lightly coat the skirt and cylinder walls with oil for initial installation.

Do not use detergent oil, synthetic oil, or an additive until the rings have seated. 6. Inspect all piston ring gaps to ensure they are according to spec. 7. Replace the pistons with the Piston Kit and Piston Ring Set.

a. Install the 3 piece oil ring set on to the bottom most oil ring groove first. Begin with the expander ring. IMPORTANT: When installing, ensure the end faces of the scalloped expander ring are facing upwards as shown.

Top of Engine

b. Install the top and bottom oil control rings (or rails) into the oil ring groove, following the Ring Orientation Diagram for ring gap spacing.


c. Install the middle compression ring into the middle ring groove of the piston. IMPORTANT: Orientation of this ring is critical. The beveled edge on the ID of the ring should face downward. A small dot or depression located on the face of the ring should be facing upward.

d. Install the top compression ring on the top most ring groove of the piston. 8. Lube the new piston assembly very lightly with engine oil 9. Install pistons, making sure to note directionality as indicated on piston heads 10. Be sure to lubricate pins with Lubriplate, or an assembly oil to prevent galling on initial fire-up.

5.5 Ignition Coils

1. Screw in the threaded extension rod. Slide on washer and sleeve over extension rod. Make sure all extension rods are even across the engine and that no more than an inch extends above the sleeve.

2. Insert the coil into the spark plug tube and make sure it’s fully seated past the taper of the sleeve. Screw on the extender plate.

3. Slide on washer, thrust washer, and nut on to extension rod and tighten.

4. Attach wiring harness to all coils once assembly is complete.

5.6 Sensors

NOTE Excessive oil consumption will rapidly contaminate and physically clog the sensors’ internal structure. Omnitek recommends oil consumption of less than 0.7L/1000km (~2 US pints/1000 miles).

UEGO and Exhaust Temperature Sensors The UEGO and Exhaust Temperature Sensors are located close to the turbo on the exhaust pipe. When clamping the exhaust flanges together ensure there are no leaks upstream of the sensor. An exhaust leak upstream of the Oxygen sensor will cause incorrect sensor readings.

Procedure 1- Find a suitable location to install the sensor bung on the exhaust

system. It is recommended that the weld boss be installed approximately 12” - 18” after the turbo and before the catalytic converter for the UEGO, and 15” – 30” for the Exhaust


Temperature Sensor. Never install the sensor in the exhaust manifold between the cylinder head and the turbo.

2- Determine the orientation of the weld boss. Ideally the

sensor should be oriented at 10 - 15 off the vertical (12 o’clock) position. However, depending on engine configuration the sensor can be installed where necessary between the 9 o’clock and 3 o’clock positions, taking care not to install them directly vertical or horizontal.

3- Verify that you have adequate clearance for the sensor and wiring harness before installing the

weld boss. 4- Once the weld boss is complete,

apply anti-seize to the threads of the oxygen sensor, making sure to not contaminate the tip.

5- Insert the oxygen sensor and torque to 34-36 ft-lbs (46-50 N-m).

The image shows a good location for installation of these sensors. View is looking at the back of the engine from inside the cab, with the engine cover removed. Since the UEGO sensor is located on the downpipe, the angle of installation is not critical.

The coolant temperature sensor should be installed at the end of the coolant manifold. Before installation, clean the flange surface of the inlet manifold. Apply pipe sealant to the threads, screw into the manifold, and tighten with a ¾” box end wrench.


HEGO (aka 4-Wire Oxygen Sensor) and Secondary Exhaust Temperature Sensor

The HEGO and Secondary Exhaust Temperature Sensor are located on the Catalytic Converter. Both sensors also need to be clocked such that they are 10-15º off the vertical and horizontal positions. The sensors should be installed a ½ turn past finger tight.

5.7 Catalytic Converter

The Catalytic Converter should be installed approximately 3-4 ft after the turbocharger and no more than 6’ from the exhaust. Installing the converter further away from the turbocharger will significantly effect emissions and is not allowed.

The picture below depicts the location. When installing the converter, make sure the sensors are clocked in positions that are approximately 10 – 15º off the vertical or horizontal positions.


WARNING Immediately shut off the engine if a misfire develops. An engine misfire condition will severely damage the catalytic converter.

5.8 Air/Fuel Module

The gas injection manifold is a critical component of the fuel delivery system. Ensure cleanliness of this part for proper fuel mixing.

CAUTION The injector manifold is an engineered, pressurized component with multiple internal passages. Modifications to it such as drilling or tapping are not authorized. Mount the manifold using only the mounting holes and hardware provided.

CAUTION Use only approved gas supply hoses obtained from Omnitek. These hoses are specifically engineered for chemical and physical resistance to the harsh environment they need to survive in. For the safety of the installation, do not substitute inferior gas supply hoses or attempt to alter the length of a hose in any way.

NOTE When cutting hosing, make sure to blow out debris from the tube before attaching it to the engine system. Cutting material in the hose can severely damage the engine.

The installation of the Throttle Body and Injector Manifold/Mixing Ring on the Air Fuel Module is directional. Orientation of the module and associated components are important and dependent on the engine configuration. To prevent a bias of air flow from the air/fuel module, the throttle plate rotating axis must be parallel to the cylinders as shown. For more information, see attached PDF document titled “C.10683 Assembly Manual, Air Fuel Module, Mack.”

Procedure

1. Attach the silicone Intake Hose and the Manifold FuelRing Adapter to the intake manifold using two 3” Hose Clamps.

NOTE: Make sure the knob on the Intake Air Temperature Sensor that secures the wiring harness is facing down.

2. Install the Air Fuel Module. To prevent a bias of air flow from the air/fuel module, the throttle plate rotating axis must be parallel to the cylinders as shown.


3. Attach all wiring harnesses per the wiring diagram in Schematic 6.4.

5.9 Turbo Modifications

The turbo will need to be modified to accommodate the difference in power needed due to the change in fuel composition. Turbo modification is engine specific, therefore see associated documents “Mack E7 Turbo Mods” for information on how to install the engine specific model. When installing the new turbo, the exhaust pipe will most likely need to be modified to accommodate the new configuration.

5.10 CNG Regulator Mounting

In some applications, the regulator mounting location is critical and failure to locate it as specified will alter the calibration, causing degraded performance and/or emissions. The installation must be made in accordance with the code of the authority having jurisdiction, or in the absence of a local code, in accordance with the current edition of the American Standard for Compressed Natural Gas (CNG) Vehicular Fuel Systems NFPA 52.


Determine the proper location using the following criteria:

Install the unit in the engine compartment, but NOT on the engine block. Ensure unit maintains ready access for installation and maintenance. Do not place within 5” (12cm) of exhaust pipes or exhaust manifold. Do not place within 2” (5cm) of moving parts, e.g. V-belts, pulleys, etc. Do not place in splash path. Do not place on frontal sheet metal. Do not place on radiator tank. Do not install unit so that it interferes with OEM mechanical operation or where mechanical operation

endangers unit, e.g. engine rock or hood closing, etc. Do not install in areas that interfere with routine service operations, e.g. checking or adding oil or

transmission fluid, etc. Installer-made brackets are acceptable if they meet the above criteria.

In addition, the regulator must be near to your intended gas injection block location and should be situated such that the connecting hoses and low-pressure CNG filter will fit between the regulator and

t, n is rigid with no parts

nt in this location, you can mount it to the frame or

nd an alternative location using the above criteria.

ected in parallel with an existing

gine is running. Some coolant lines

en must have enough pressure drop across them to flow coolant through the

the injection block.

You may need to fabricate a bracket to mount the regulator. Paint it to protect it from corrosion, and useplated fasteners. Ensure that the regulator body is not stressed when the regulator is mounted to the brackeand make sure the installatiorubbing against each other.

The image above shows a good location for installation. This location is on the driver’s side of the enginebay, near the frame rail. If an air compressor is presefi

CNG Regulator – Gas and Coolant Connections

The regulator requires heat to keep it from freezing as the CNG expands from high pressure to a usable lower pressure in the engine control system. This heat is supplied by hot engine coolant. Vehicles have varying coolant hose routings and functions. The regulator coolant ports are connengine coolant circuit as shown.

You must select coolant hoses using the following guidelines:

There must be coolant flowing in the lines at all times when the enonly conduct coolant after or before the engine thermostat opens.

The coolant lines chosregulator even at idle.


The regulator will divert some coolant flow away from the original function of the hoses. Ensure that this is acceptable and that installation of the regulator does not compromise a critical vehicle function such as transmission oil cooling.

Do not selecto

normal operat

a coolant return point that diverts the coolant directly to the radiator, bypassing the stat. This will provide cooling at all times which will not allow the engine to reach its ing temperature.

engine therm

CAUTION some engines at high

heat transfer passages.

Do not plumb the regulator in series with a coolant line. The relatively high restriction of the regulator and the high coolant pump output onspeed will cause a large pressure drop across the regulator. This will impede the original function of the coolant circuit and the fast-flowing coolant may induce erosion and cavitations of the regulator

TIP: Vehicle interior heating hoses are often a good choice for regulator heating. They are large diameter and high flow, and the diverted coolant is not significant.

When you have chosen the coolant tap locations according to the above criteria, install the coolant

the engine to check for leaks. If the coolant has been drained air pockets may prevent the

plumbing as shown above.

1. Secure all coolant hoses to fittings and tees with the supplied clamps. Do not over tighten clamps.

2. Refill coolant system or unclamp hoses. Check and eliminate any coolant leaks.

TIP: Be careful running coolant pump from properly circulating the coolant resulting in possible overheating and engine damage. Check coolant level after engine has cooled down to ensure that the coolant level is correct.

CNG Supply Tubing

The high pressure tubing connection to the regulator uses tube compression fittings. Depending on the

ly. Blow out the tubing with compressed air before connecting to eliminate all debris.

e relieved in the tubing area

application, your system will use 6mm, 8mm, 10mm, 1/4”, or 3/8” tubing diameter fittings. Ensure that the fitting diameter matches the tubing diameter. 6mm and 1/4" are especially close in size but mixing will not allow a secure installation. Note the following:

Ream and clean the tube end careful

Ensure that stresses ar and that the tubing will not be flexed, stressed or abraded in any operating condition.

5.11 Wastegate Solenoid

The Wastegate Solenoid is connected to the Wastegate Actuator and the intake system using flexible rubber tubing. The Wastegate Actuator is installed on the internal-wastegated turbocharger. A more detailed diagram is shown in Schematic 6.3. Install the turbo Boost Pressure Sensor, Wastegate

olenoid and Wastegate actuator upstream of the Throttle. anifold Pressure Sensor, Pressure Regulator, and

low off valve (if used) downstream of the Intake Manifold.

SInstall the MB


5.12 Wiring Harness

When installing the wire harness, follow your application-specific wiring diagram for correct connection and installation. See Schematics 6.4 and 6.5 for reference. Ensure you have the correct wiring diagram for your application before you begin installation.

Before installing the wire harness disconnect the ground terminal on the battery.

Do not route near hot spots such as exhaust components. Do not route near belts, pulleys, fans, or any other moving parts. Do not route wiring with high-tension ignition coil leads.

CAUTION Do NOT route any wiring harness leads within 8” of an ignition lead. Doing so can cause voltage spikes in the harness which could damage any electronic components. Such failures are not covered by warranty.

Do not route wire next to sharp edges such as those on sheet metal brackets and body panels. Do not route wire in any area where it may be splashed or dripped on with chemicals. Some

chemicals, particularly Power Steering Fluid can damage the insulation on the wires. Fasten wires down with tie straps and cable clamps. Do not allow wires to hang loose especially from

terminating devices. Tie the harness down at regular distance intervals and provide it with some form of strain relief in close proximity to the end connector.

CAUTION Electrical connectors, particularly the ECM main connector, will withstand a limited number of insertions before the terminals become unreliable. After 50-100 insertions the connections may cause erratic, difficult to diagnose conditions. Replace connector terminals if connectors have been repeatedly inserted and removed, or if they are contaminated with dirt, oil or other substances.

Some connectors, connector cavities or loose wires may not be used for your particular application. Any unused connectors or connector cavities must be properly capped using the mating connector with cavity plugs in all unused cavities. Loose wires must be cut to a short length and capped by heating a small length of heat shrink on the end of the wire and pinching it with pliers before it cools. The wire should then be tucked into the Wire Harness loom and secured using tie straps.

Correct unused lead termination

Installation

Before starting, make sure all CNG storage cylinders are closed and high pressure CNG lines are all drained. When connecting the wiring harness to its end devices, follow your application-specific wiring diagram to ensure the wire colors match the specified components.

The best place to start for your power connections is the fuse box. Almost all the powered components on the vehicle get power from this location. Here are some instructions for selecting power sources:

For Unkeyed Power, find an uninterrupted vehicle voltage source. This will connect to the Orange ECU wire. Toggle the key through all positions, including the “OFF” and “Start” positions, while measuring the voltage of your selected source. There should be no interruption in the power supply. Do not connect this wire directly to the battery as this is a common point for extreme corrosion,


which may cause the wire to break. The ECM system will draw up to 1 Amp from this wire, so ensure the system you splice into can handle the extra current. The Unkeyed Power allows the ECM to retain vehicle statistics, diagnostic trouble codes and other important information when the vehicle is turned off. Use the fuse holder and the 1 amp fuse supplied to protect the circuit.

For Keyed Power, find a power source which supplies vehicle voltage while the key is in the “ON” and “Start” positions. This will connect to the Red/Green line of the ECU. Suggested possibilities for this are OEM power supply to the OEM ECM, and power to the OEM ignition coil. If an ignition power lead is selected, be sure there is no resistor between the power source and your splice. Some ignition systems use ballast resistors on the power connection to reduce peak current to the ignition coils. Splicing after this point may cause improper operation of the ECM and the ignition system. The ECM system will draw up to 10 amps from this line. Be sure the system you splice into can handle the extra current. Use the fuse holder and the 10 or 15 amp fuse supplied.

After finding power sources, select a ground source. Grounding should be done on a reliable engine block ground. Find a mounting stud on the engine block. It must match the size of your ground terminal. The most common size for ground terminals is 10 mm. It should be away from exhaust manifolds and drip or splash paths. Use only serrated heavy-duty grounding lugs. Non-serrated, inferior quality grounding lugs are a major cause of unreliable operation and electronic component damage. Damage to ECM components caused by using unapproved grounding lugs will not be covered by warranty.

Next, disconnect the ground terminal on the battery. Now, lay the harness out with connectors generally in the positions you want them. This will give you a rough idea of which connections you have to lengthen or shorten. Start tying the harness down to local components along the route of the wire harness. Good items to tie the harness to are the OEM wiring harness (provided it is properly secured), local brackets and frame members. Be sure to route the wiring for the Oxygen Sensor well away from the exhaust component it is installed into. The sensor itself has high temperature wiring but the connector and connecting harness and wire cannot withstand the temperatures associated with hot exhaust components. As the harness gets tied down, you will be able to determine exact lengths by which harness leads need to be extended or shortened.

Below is a location for mounting the relay and fuses. This area is located on the driver’s side engine bay near the fire wall


CAUTION Before re-connecting the ground terminal to the battery, check the condition of all battery, starter and alternator electrical connections and cables. If there is any sign of corrosion or a poor connection, then the terminal must be replaced or repaired. A poor connection caused by corrosion or poor connections can cause power spikes which will lead to damaged electrical components. Damage of this kind to any component in the ECM system is not covered by warranty.

NOTE DNG Engine / Vehicle Systems integration is a complicated procedure. Transmission shift points and clutch engagement operations, as well as accurate readout of dashboard gauges and OBD system warning and MILs may require OE support or access to OE workshop manuals. Access to workshop manuals and special tools is the responsibility of the DNG Engine installer not Omnitek. In some instances a transmission re-flash may be necessary as shift points may need to be matched with the natural gas engine performance characteristics.

5.13 ECM

Once the wiring has been checked, connect the ECM using the following procedure:

1. Disconnect the battery ground terminal and close the manual valve on the fuel tank. 2. Connect the wiring harness header connector to the ECM. 3. Re-connect the battery ground terminal.



CAUTION Do not connect the ECM directly to a vehicle with a vehicle voltage above 12v (remember, 12v automotive electrical systems have a nominal vehicle voltage of 13.8v). If you are installing a ECM system on a vehicle with a vehicle voltage above 12v, you will require a Voltage Adjusting Module and a specialized wiring harness.

In order for the ECM to display the tank pressure, a tank pressure sensor must be installed on the engine. This is not part of Omnitek’s standard conversion but can be purchased separately from a high-pressure fuel system supplier.

CAUTION The ECM system is designed to control resistive type fuel gauges only. Interfacing with multiplexed or digitally-controlled gauges may require a special application module or use of the optional Omnitek gauge. Do not attempt to connect the ECM system’s fuel gauge wiring to any type of gauge except resistively-triggered.

In most cases the fuel gauge signal wire in the ECM system wiring harness must be extended to reach the dashboard fuel gauge.

CAUTION Connecting the ECM system fuel gauge signal wire to a positive voltage source, such as the “+” wire on the gauge, will cause immediate and irreparable damage to the ECM! If in doubt, double check your connections or call Omnitek.

Malfunction Indicator Lamp

The ECM system uses a Malfunction Indicator Lamp to indicate a malfunction and a separate Engine Protection Lamp to indicate when the control system has entered engine protection mode. The lamps may be either an unused original dashboard lamp or optional lamps available from Omnitek. If an original equipment dashboard lamp is used, ensure that the circuitry used is “switched ground”, i.e. there is always vehicle voltage on one terminal of the lamp, but the lamp illuminates only when a ground on the other terminal of the lamp is established.

Ensure that the rated lamp voltage matches the vehicle voltage. In most cases, the MIL wire in the ECM system wiring harness must be extended to reach the dashboard.

TIP: Poor grounding is the most common cause of electrical malfunction on a vehicle. Ensure the ground connection is made on a reliable engine block mounting lug. Use the serrated type ground lug and ensure the ground terminal is properly strain relieved.


6 SCHEMATICS

6.1 DNG Component Locations


6.2 Ring Gap Clearances

End gaps for rails on 3 piece oil rings

Cylinder Diameter Ring Gap Tolerance

Bores under 4” 0.010 – 0.050

Bores 4” and above 0.015 – 0.055

End gaps for compression rings

Ring Diameter Ring Gap Tolerance

3 – 4” 0.012 – 0.022

4 – 6” 0.016 – 0.026

6 – 7” 0.020 – 0.032

6.3 Vacuum Hose Routing


6.4 Wiring Schematic


6.5 J1939 Connectors Diagram


6.6 Removing and Installing Spark Plugs


6.7 Spark Plug Failure Modes


6.8 Oxygen Sensor Failure Modes


7 REFERENCES

Unit Conversions To Convert From Into Multiply byCelsius (ºC) Fahrenheit (ºF) (ºC x 1.8) + 32meter (m) foot 3.28meter (m) inch 39.37Pascal (Pa) Bar 1 x 10-5

Pascal (Pa) pounds / sq. inch (PSI) 1.45 x 10-4

Pascal (Pa) atmosphere 9.87 x 10-6

Pascal (Pa) kiloPascal (kPa) 0.001kiloPascal (kPa) Bar 0.01kiloPascal (kPa) pounds / sq. inch (PSI) 0.145kiloPascal (kPa) atmosphere 9.87 x 10-3

kiloPascal (kPa) Pascal (Pa) 1000

Metric Prefixes Giga (G) Mega (M) kilo (k) deca (de) Base Unit deci (d) centi (c) milli (m) micro (µ)

1 000 000 000 1 000 000 1000 10 1 0.1 0.01 0.001 0.000001

109 106 103 102 101 10-1 10-2 10-3 10-6

Example: 3.2 m (meter) = 3200 mm (millimeter) = 0.0032 km (kilometer).


Acronym MeaningECM Engine control moduleHO2S Heated Oxygen sensorECTS Engine coolant temperature sensorIATS Intake air temperature sensorIAC Idle air controllerMIL Malfunction indicator lampLPSO Low-pressure shut-off (valve)FPS Fuel storage pressure sensorFTS Fuel temperature sensorDTC Diagnostic trouble codeCMP Camshaft speed sensorCKP Crankshaft speed sensorMAP Manifold absolute pressureNPT National piper taper (thread)ORB O-ring boss (SAE J475)DIC Distributorless ignition controllerTPS Throttle position sensorMAF Mass airflow (sensor)

Torque Specification

Dash Size Minimum Maximum-4 20 Nm 22 Nm-5 24 Nm 27 Nm-6 33 Nm 35 Nm-8 68 Nm 78 Nm-10 98 Nm 110 Nm

SAE O-Ring Boss (ORB) Steel Fittings

Dash Size Minimum Maximum-4 13 Nm 15 Nm-5 18 Nm 20 Nm-6 23 Nm 26 Nm-8 47 Nm 52 Nm-10 69 Nm 72 Nm

37º and 45º Flared Steel Fittings

Automotive Acronyms


8 ENGINE CHECK LIST

To be performed after engine conversion

Date: _______________ Engine Conversion Number: ____________________

Visual Inspection: Oil Leaks : Yes No

Engine run-in/tested at factory: Yes No How long: _________ minutes / miles

Ignition timing set to exact specification: Yes No Idle: __________ Degrees BTDC

Cylinder head bolts re-torque after run-in/test: Yes No Torque: _____ Nm

Valve adjust after run-in/test: Yes No Engine Hot Cold

Intake: ______ mm Exhaust: ________ mm

Compression Test within specifications: Yes No (cylinders within 5 - 7 % of each other)

Cyl. #1 ______ Cyl. #2 ______ Cyl. #3 ______ Cyl. #4 ______ Cyl. #5 ______ Cyl. #6 ______

Cyl. #7 ______ Cyl. #8 ______ Cyl. #9 ______ Cyl. #10 ______ Cyl. #11 ______ Cyl. #12 ______

Vacuum Signal at Idle: ______ psi Charging System Voltage: ______ Volts

ENGINE PASSED: Yes No

Remarks: _______________________________________________________________________

_________________________________________________________________________________

Inspected by: Name ____________________________

Mack E7

Cylinder Head Modification Instructions

C.10612, Mack E7 Cylinder Head Mod Instructions Page 1 of 10

Parts List

Part Number Photo Component D.10609

Head Drill Guide

½” x 12” Drill Bit

M14x1.25 Tap

D.10610

Head Tap Guide

D.10611

Valve Cover Drill Guide

3/8” Drive Tap Socket

¼” x 12” Drill Bit

1 3/8” Hole Saw Assembly


D.10495

Spark Plug Tube

1061T77

1x3/8x1/16” Grommet

9452K75

SAE –021 O-ring

10 090 007

Omnitek Spark Plug


1.0 Set Up

NOTE Before beginning assembly, ensure work bench and surfaces are clean of all dirt, oil, and debris. Check the assembly kit contents against the parts list and gather all tools needed.

NOTE This is a general assembly guideline. The tools may look slightly different or your assembly kit may vary depending on your engine needs.

Additional items needed, not included in package:

M10 screws to hold down drill and tap guides Anti-seize for the spark plug threads Parker O-Ring lubricant SLUBE-884-2-TFD for the O-Ring High-Temp RTV silicone Cutting oil for drilling/tapping Sanding tool for the valve cover OEM Manual for engine disassembly and reassembly

Disassemble the Engine Refer to the OEM manual for detailed engine disassembly procedures. Follow the OEM specifications and procedures for removing all components and keep parts for reassembly. For items such as the valve springs, mark the orientation to ensure the correct configuration during reassembly. Check for any wear or damage on components and replace or repair as necessary.

IMPORTANT: Inspect the head for heat stress, cracks, distortion, warped head & block, erosion/blockage of the galleries, passages, etc. for oil and coolant. Replace or repair if found. 2.0 Remove Injectors

1. Remove injectors per OEM manual. 2. Clean the area and the passages of rust and debris using a carbon steel wire brush. 3. Clean all of the newly exposed areas of oil and debris using a solvent and rag. This will help to

maintain the set-up accuracy.


3.0 Drill the Cylinder Heads

1. Install the Head Drill Guide (#D.10609) into the cylinder head. 2. Install an M10 screw to hold down the guide. 3. Use cutting oil to lubricate the ½” Drill Bit and cylinder head. 4. Drill through slowly and do not force the bit.

*Optional Method: The hole can also be drilled using a mil.


4.0 Tap the Cylinder Head

1. Install the Head Tap Guide (#D.10610) into the cylinders. 2. Install an M10 screw to hold down the guide. 3. Lubricate the tap using a thread cutting lubricant. 4. Insert the M14x1.25 Tap 5. Using the 3/8” Drive Tap Socket, tap the cylinder head. 6. De-burr the machined area, paying attention to the combustion chamber side. Any sharp edges

in the combustion chamber can become hot spots and can cause pre-ignition.


5.0 Grind the Valve Cover Ribs Prior to drilling the holes in the valve cover, the reinforcement ribs where the holes will be drilled need to be ground flush. This makes the drilling process easier and prevents the drill bits from deflecting.

1. Locate the areas in the valve cover above where the cylinders are located and where the reinforcement ribs meet.

2. Using a sanding disk, end mill, or similarly appropriate tool, remove the ribs in an area approximately 2.5” in diameter, using the cross section as the center of the circle.

2.5”

3. Sand the area as flush to the base section as possible, being careful to not remove too much

material and risk the integrity of the valve cover thickness. Note: If after drilling the holes in the valve cover and installing the grommets, the ribs or other material contact and/or cause deformation in the grommet, re-sand that area to remove the material. Any problems with the seal of the grommets could lead to oil leakage during engine operation.

Ribs not ground properly can cause bulges in the grommet and jeopardize the seal in the valve cover.


6.0 Drill Pilot Hole in Valve Cover

NOTE While performing the valve cover drilling, take care not to damage the head in any way. Protect the gasket and machined surfaces throughout the procedure. In addition, protect all sealing, O-ring, and gasket surfaces.

NOTE It is important to perform each of the steps to all three cylinders at the same time to ensure efficiency and accuracy of drilling. Once the first pilot hole is drilled, do not remove the valve cover until the last hole-saw drilled hole is completed.

1. Install the Valve Cover Drill Guide (#D.10611). 2. Install the M10 screw to hold down the guide. 3. Install the valve cover gasket and valve cover. 4. Torque each valve cover bolt according to OEM specifications. 5. Turn the head, so that the valve cover is away from the technician. You may need to rest the

head on wooden blocks or otherwise adjust the work bench to make the drilling process easier. Precision for this step is critical.

6. Starting at the combustion chamber side of the head, drill a pilot hole through the valve covers using the ¼” x 12” Drill Bit. It is recommended that the drill bit be lubricated before this procedure to ease cutting and prolong the life of the bit.


NOTE The accuracy of this next cut is critical. Ensure all components are properly aligned and secure before drilling.

7. Turn the head, so that the valve cover is toward the technician. 8. Insert the 1-3/8” Hole Saw Assembly through the valve cover and into the Valve Cover Drill

Guide. 9. Drill slowly and carefully through the valve cover. Do not force the hole-saw and bit. If it

wanders it may cause problems with sealing the area. 10. Once complete, disassemble the set-up, and clean all parts before moving to the next step.



7.0 Final Assembly

NOTE Remember to always use anti-seize when installing spark plugs to assure easy removal and prevent corrosion and seizing.

1. Coat the spark plug threads with anti-seize and install into the cylinders. 2. Torque the spark plugs to 18-23 ft-lbs. 3. Lubricate the Omnitek O-ring (#9452K75) with Parker O-Ring lubricant SLUBE-884-2-TFD

and install on the Spark Plug Tube (#D.10495). 4. Apply High-Temp RTV silicone to threads of the Tube and screw into cylinder head. Slide an

appropriate tool into the slots in the top to tighten slightly more than hand tight. 5. Install the Grommets (#1061T77) on to the valve cover to seal the Spark Plug Tubes.

SPARK PLUG TUBE

6. Install Omnitek supplied valve train components (valves, seats and guides) and modified valve cover to engine block.

7. Follow Omnitek instructions and specifications for new natural gas components. 8. Reassemble remaining components according to OEM specifications.

Assembly Manual

Air/Fuel Module Mack E7

C.10683, Assembly Manual, Air Fuel Module, Mack E7 Page 1 of 8

DETAILED ASSEMBLY DRAWING

11

10

12

13

14

19

20

9

5

4

3

2

1

15 7 6 8

1716

18


DETAILED PARTS LIST – 175-6683.5 Item Description Size Part Number Quant

1 Throttle Body Adapter VMack, AC, Etech D.10520 1

AI Configuration D.10493

2 Dash 6 Hose Barb D.10004 1

3 FuelRing Gasket 68mm D.10057 1

4 FuelRing 68 x 6 D.10550 1

5 Throttle Body Gasket 68mm D.10139 1

6 Nylon Lock Nut M5 93625A200 4

7 Flat Washer M5 91166A240 8

8 MAP Sensor and TBP Sensor 3 bar 10 114 013 2

9 MAP Sensor Brackets 68mm D.10364 2

10 Hex Head Cap Screw M5x.08x30mm 91280A238 4

11 Socket Head Cap Screws M6x1.0x50mm 91292A144 8

12 Lock Washer M6 91202A234 4

13 Electronic Throttle Body 68mm 10 020 068 1

14 Gas P/T Sensor 12 bar 10 117 087 1

15 Injector 10 130 600 6

16 Injector Center Bracket 780.29.IG6.007 4

17 Injector Side Bracket 780.29.IG6.006 4

18 Hex Head Screws M4 920.00.M04.006 16

19 Dash 6 Plug 50925K435 1

20 Intake Air Temperature (IAT) Sensor 10 117 084 1

* For AI configuration, IAT is on engine ADDITIONAL ITEMS NEEDED Socket wrench and socket kit (3/4” and 15/16” sockets used) Allen wrenches Adjustable crescent wrench Parker O-ring Lube NOTE: When assembling the air fuel module, make sure the workspace and hands are

clean of debris and oil. Before beginning assembly, inspect all components for any signs of damage, and ensure the butterfly valve is in working condition and rotates freely.


PROCEDURE A. Install side components

1. Lubricate both brown O-rings and install on to High-Flow Gas Injector.

2. Push injector into FuelRing until fully seated.

3. Repeat procedure for additional injectors. 4. Install the Injector Center and Side Brackets and secure with the Hex Head Screws.

5. Lubricate the O-ring for Dash 6 Plug and install. Screw plug in to the port on the side of

the FuelRing that will not contain the fuel line. Tighten using allen wrench.


6. Lubricate the O-ring on the Dash 6 Hose Barb and install. Screw on to the other port of the FuelRing that will contain the fuel line. Tighten using crescent wrench.

7. Lubricate the O-ring on the Gas Pressure/Temperature (P/T) Sensor and install. Screw the

sensor into the port on the top of the FuelRing and tighten with a 15/16” socket wrench.

8. Screw in the Intake Air Temperature Sensor to the Throttle Body Adapter and tighten with a ¾” socket wrench. Make sure the knob where the wiring harness attaches to the sensor is facing down/ towards where it will attach to the Intake Manifold.

Note: For AI Configuration, the Intake Air Temperature Sensor is mounted on to the engine, and is not included in this assembly.

9. Attach the MAP Brackets to the MAP Sensors using the Hex Head Cap Screws, M5

Nylon Lock Nuts, and M5 Flat Washers as shown.


B. Install FuelRing/Mixer Gasket NOTE: Orientation of the gasket is extremely important! Double check the orientation

of all components before completely assembling the module.

1. Determine orientation of the FuelRing/Mixer Gasket. The side of the FuelRing gasket with continuous gas entrance ports (most airflow) needs to be on the side of the butterfly valve that rotates into the Air Fuel Module Assembly.

Valve rotates into Air/Fuel Module when assembled

Once the orientation of the gasket has been established, it will need to be sandwiched between the FuelRing and the Throttle Body Adapter.


2. Place the Throttle Body on to the FuelRing in the orientation in which it will be mounted. The Throttle Body should be configured so that it resembles the figure below when fully assembled.

3. When orientation is established, center the gasket on the FuelRing. The gasket has two ears along the outer diameter. These ears normally align with indents in the FuelRing, however for some FuelRing configurations the indents do not match up.

Tab

Indent

*The ears on the gasket must be cut off if they do not line up with the indents to ensure proper seating of the assembly.

4. Once the gasket orientation has been determined and seats properly in the FuelRing,

secure the Throttle Body Adapter (with the Gas P/T Sensor on the same side as the Dash 6 plug) using the Socket Head Cap Screws.

AI Configuration:



C. Install the Throttle Body 1. Slide the MAP Sensors and brackets on to the two open sides of the Throttle Body.

2. Place the Throttle Body Gasket on to the Throttle Body where it will connect to the FuelRing.

3. Position the Throttle Body assembly on to the FuelRing and secure using the Socket Head Cap Screws and M6 Lock Washers.

C.10649, Engine Conversion Finalization Page 1 of 7

Omnitek Engine Conversion Finalization

Engine Label Placement

All labels supplied by Omnitek must be installed on the engine or truck with specific location requirements. Please read the following instructions for each label when determining placement. In addition, always clean the area thoroughly where the label is to be affixed with a shop rag or mild detergent if necessary. It is important to affix labels securely to ensure lasting adherence to the vehicle to meet EPA requirements. OEM Emission/Engine ID Label: This label will need to be transferred or recreated to attach to the newly converted engine. If the old OEM label is on a component that is NOT modified during the conversion process and is still legible and undamaged, it can remain in place. If the old OEM label is located in an area affected by the conversion (such as the valve cover, engine block, or crankcase), is missing, illegible, or damaged in any way, a new label will need to be purchased. Contact Omnitek to supply necessary engine information so that a new label may be obtained to meet all EPA requirements. This new label should be affixed in its original location, or be clearly visible such as on the Valve Cover.

Supplemental Emission Compliance Label: This label must placed near the OEM Emission Compliance Label on the engine so that it is clearly visible. These labels are made of a non-removable, non-transferrable material. It will tear if any attempt is made to remove it once the label has been properly installed.


If the label becomes damaged during installation, contact Omnitek Engineering Corp. for a replacement and retain the damaged label. The damaged pieces will need to be returned to Omnitek as part of the document control process required by the EPA. A clear label goes over the actual label to protect the label and text against dirt and oil.

Warranty Placard: This metallic placard needs to be installed on the driver side door jam near the OEM vehicle identification label. This placard is very important as it has the warranty number written on it and is used to register the engine with Omnitek for warranty eligibility. Registration must occur within the first 30 days after engine install. The engine is registered with Omnitek under this number. Without this number, Omnitek may deny warranty.

Vacuum Schematic: This label needs to be placed on the engine or firewall (bulkhead) of the truck so it is visible for the servicing technician. It is recommended that it be located next to or near an OEM label or schematic that provides similar information for


the servicing technician. Do not place label on any removable part such as the cowling, batteries, wheel well, etc.

Engine Maximum Temperature Indicator: The Indicator is used to show the maximum temperature that the cylinder head was exposed to during operation. It will help determine if the engine experienced an extreme temperature or loss of coolant that could result in engine damage. This label needs to be positioned on the cylinder head away from the exhaust manifold, turbo charger or other source of high temperature. If this label is not present, Omnitek may deny warranty claims as a result of an overheated engine or cylinder head gasket leak.


Final Check and Start Up

Engine Pre Check 1. Check for leaks in all hoses, fittings, gasket surfaces and connections. 2. Check all fluid levels prior to starting the engine. If any fluid level is below recommended

amount, add fluid to proper level. 3. Inspect for loose or disconnected electrical connectors or wires. 4. Connect the OmniWatch USB cable to the ECM and to a computer.

OmniWatch Software Setup For assistance in navigating the OmniWatch software refer to the OmniWatch Software Manual, provided separately. Calibration 1. Put the ignition key in the ON position, but do NOT attempt to start the engine 2. Start the OmniWatch software 3. Contact Omnitek to have ECM programmed online (OmniWatch and internet connection

required). Omnitek will program the ECM with the appropriate engine calibration file, based on the following engine specifications: Vehicle Model & Year Engine Family Engine Horsepower Engine Torque

4. Once calibration is complete, turn the ignition key OFF and wait until the ECM has completely shut down – this can take up to 1 minute.

For Omnitek certified installers only, to perform the ECM programming manually:

a. Connect the PC-Link to the ECM (press F9) b. From the ECM menu, select Program Firmware c. Select Open button and select newest firmware file (with file extension “.bi”) d. Select Program ECM button and allow OmniWatch to program the firmware e. Cycle key switch to the OFF position for 30 seconds. f. Connect the Data-link adaptor to the PC-Link connection on the wire harness near the

ECM g. Connect the Data-link adaptor to the USB port on the diagnostic laptop h. Turn the key switch to the ON position i. Open the OmniWatch Diagnostic Software j. Connect the PC-Link to the ECM (press F9) k. Form the File menu, select Open Calibration File from Disk l. Select calibration file and click on the Open button m. From the ECM menu, select Send and Save Calibration Tables to Permanent ECM

FLASH and allow ECM to complete the action n. Cycle key switch to the OFF position for 30 seconds.


Setup 5. Turn the ignition key ON, but do NOT start the engine. 6. Establish communications with OmniWatch and ensure all sensors are reading correctly on

the sensors screen. DO NOT START THE ENGINE. 7. Ensure that the correct firmware and calibration files are installed. 8. Check for DTCs (F6) and diagnose and correct as required. (During the first startup it is

normal to have some DTCs – clear all). 9. Proceed to the Setup and Calibration Screen [F5]. 10. Use the pull down menu and select “Run Throttle Zero/Span Cycle” to span the electronic

throttle body. This procedure must be performed to eliminate any variations in calibration between throttle bodies. Follow the on-screen instructions.

11. Check for DTCs after this procedure and diagnose/correct as required. 12. Put the ignition key in the OFF position and wait until the ECM has completely shut down –

this can take up to 1 minute.

Initial Start Up 1. Before starting the engine, check all fluid levels and inspect the vehicle to ensure it is safe to

be operated on public roadways 2. Do NOT depress the accelerator pedal 3. Cycle key switch to ON position and allow dash gauges and ABS system to power up 4. Start the engine again and allow to idle for 10 minutes. During this time, check for any signs

of abnormal engine operation. Some important items to check for are: Unstable Idle Engine Noise Oil Leaks Water Leaks Diagnostic Trouble Codes Check high-pressure storage cylinders, fuel supply lines, valves and all fittings for leaks.

Using a leak detection soapy spray, check for bubbles. Refer to Manufacturer’s instructions on repair procedures and tightening processes to repair any leaks.

9. Allow engine to continue to run until coolant temperature has reached normal operating temperature and the engine fan has engaged around 183ºF. Correct any issues discovered before continuing to run the engine. Note As the exhaust system heats up, you may observe excessive smoke coming out of the

exhaust pipe, getting worse as the exhaust system/muffler heats up. This is due to the accumulation of oil in the system over the years and is not of concern. This condition may last up to 100 miles.

Road Test 1. Drive the truck on a route that include both city and highway driving and some mountainous

terrain if possible. 2. Observe performance of engine. Listen for any abnormal noises, backfires, misfires, etc. 3. Check the DTC (F6) screen for new set codes using OmniWatch diagnostic software.


WARNING Never operate the engine with any misfires present as an engine misfire condition will severely damage the catalytic converter. If a misfire develops, immediately shut off the engine.

Other System Components Vehicle Charging System and Battery

The battery must have sufficient Amp-hr capacity to assure easy starting even in very cold weather. Normal working voltage should be between 12 and 14.5 Volts. Minimum voltage during starting must not go below 10 Volts. Maximum short time voltage spikes may not exceed 16 Volts.

Verify that charging system is in good working order. High charging voltage can damage EMS components. Low battery voltage may not be enough to start engine.

Cylinder Compression

Balanced cylinder compression is very important for power and emissions. If the compression is low in one or more cylinders, engine power will also be low and the engine will run roughly.

All cylinders must be within 5 - 7 % of each other.

Engine wiring harness

CAUTION Do not route any wiring harness leads within 4” of an ignition lead. Doing so can cause RFI spikes in the harness which could damage any electrical components. Such failures are not covered by the warranty.

Do not route wires near hot spots such as exhaust components. Do not route wires near belts, pulleys, fans, or any other moving parts. Do not route wires next to sharp edges such as those on sheet metal brackets and body

panels. Do not route wires in any area where it may be splashed or dripped on with chemicals.

Some chemicals, particularly Power Steering Fluid can damage the insulation on the wires.

Check and ensure the connections are as per wiring diagram. Ensure the end connections are properly fixed and are not in any way strained. Assure all grounding points are secure and free of paint or debris. Fasten wires down with tie straps and cable clamps. Do not allow wires to hang loose

especially from terminating devices.

Ignition system Ensure ignition coils are securely mounted. The ignition coil low-tension wires (primary wires) and high-tension spark plug wires are

to be routed and clamped securely.


Ensure proper connection when installing spark plug wires to the coil. This is a tight fit and there will be a clicking sound heard.

Ensure that the spark plug connectors are securely affixed to the spark plugs and that they are symmetrically in the cylinder head.

Ignition Timing

Ignition timing is preset and NOT adjustable. At Idle: 750 RPM, 15 degrees BTDC

General Guidelines

Never arc-weld on any vehicle with the ECM connected. Never leave fuel lines open. Fuel lines must be capped at all times to prevent fuel system

contamination. Never paint any EMS components (sensors, connectors) or grounding points. Motor oil specially formulated for natural gas engines must be used. Engine thermostat must remain installed at all times. Coolant system must be filled with Antifreeze. A generic OBD scan tool can be used to check and clear DTCs.

MACK E7, 1994 - 2006

Diesel Engine Converted To Natural Gas

Operation & Maintenance

Omnitek Engineering, Corp. 1333 Keystone Way, #101

Vista, CA 92081 Tel. 760-591-0089 Fax. 760-591-0880

www.omnitekcorp.com

©Copyright Omnitek Engineering Corp. 2013

http://www.omnitekcorp.com/

Table of Contents General Safety Guidelines.............................................................................................................................3 Emissions ......................................................................................................................................................3 Operational Guidelines..................................................................................................................................4

Break-in period for the Engine................................................................................................................. 4 Engine Speed Limitations ........................................................................................................................ 4 Starting ..................................................................................................................................................... 4 Shut Down................................................................................................................................................ 5 What NOT to do....................................................................................................................................... 5

Start-up Procedure after Extended In-operation ...........................................................................................5 Inspection ......................................................................................................................................................5 Maintenance ..................................................................................................................................................6

Lubricant & Grade ................................................................................................................................... 6 Oil Viscosity Identification.................................................................................................................. 6 Oil Change Interval .............................................................................................................................. 6 Oil Filling Volume ............................................................................................................................... 6 Oil Consumption .................................................................................................................................. 7

Coolant ..................................................................................................................................................... 7 Adjusting the Valve Clearance................................................................................................................. 7 Ignition Timing: ....................................................................................................................................... 7 Spark Plugs .............................................................................................................................................. 7

Spark Plug Change Interval ................................................................................................................. 7 Maintenance Schedule ..................................................................................................................................8 OMNITEK ENGINEERING CORP. LIMITED WARRANTY POLICY.Error! Bookmark not defined.

C.10646, 8/5/14 Mack E7 Service & Operation Manual

2

Introduction This manual provides technical references and instructions regarding operation and maintenance of the Omnitek Engineering Corp. Diesel Engine Converted to Natural Gas (DNG). Please read this manual carefully. Only by strict observation of all operation and maintenance requirements will the Warranty be in affect and a long service life of the engine can be expected. This manual offers only instruction on the operation and maintenance of the newly converted DNG engine. For maintenance procedures and instruction on the vehicle, please contact the vehicle manufacturer or refer to the vehicle owner’s manual for detailed operation and maintenance instruction. NOTE From time to time, Omnitek may issue a recall of the engine to repair certain defects without

charge to the customer. The customer must return the engine (or vehicle) to an authorized Omnitek Service Center promptly for all warranty guarantees to remain in effect.

General Safety Guidelines

1. Observe all federal, state, provincial or local regulations regarding the servicing of natural gas vehicles.

2. The engine can only be applied within the designed service range as discussed with Omnitek. 3. The power rating and emission standard of the engine cannot be altered. 4. All modifications and operation of the DNG engine must be performed by qualified personnel. 5. All unqualified personnel must maintain a safe distance while the engine or accessories are

running. 6. Do not wear loose articles of clothing or be near moving components during operation. 7. Never open the filling cap of the cooling system while the engine is still hot. 8. Always assure the battery and charging system is in good condition. 9. Charging the battery generates flammable gas. Neither sparks nor fire are allowed near the

battery. 10. Disconnect the positive and negative terminals of the battery before doing any work or welding

on the electrical system. 11. Gloves are recommended during maintenance and operation to protect skin from damage caused

by oil. 12. Ensure the gear lever is in the “neutral” position before starting engine. 13. Use only parts and fittings supplied through an Omnitek Authorized Dealer when doing repair

work. 14. Exhaust Turbocharger operates under high speed and high temperature conditions. Keep

appendages and tools away from the air inlet and outlet of the turbocharger. 15. Venting of high-pressure storage cylinders or fuel service lines should not be performed inside a

building at any time. Emissions The DNG Conversion System and Engine was designed to comply with all applicable emission standards and comes equipped with a 3-way catalytic converter. If a misfire develops, immediately shut off the engine. An engine misfire condition will severely damage the catalytic converter.


3

Operational Guidelines

Break-in period for the Engine 1. The break-in period for this engine is 3000 miles. 2. During this period, do not use full engine speed or fully load the vehicle for prolonged periods. 3. After the break-in period the engine can be operated at full load as soon as the engine reaches the

minimum temperature of 60°C (140°F). 4. Do not operate the engine at high speed without a load. 5. Do not overload the engine. 6. Replace the oil at 2000 miles during this period.

Below is a chart indicating the recommended load capacity throughout the break-in period.

Mileage on new engine Engine Load Capacity 0 – 200 miles Unloaded running, engine speed less than

1800RPM 200 - 1500 miles Medium Load 1500 -3000 miles ¾ Load

Due to the power characteristics of the turbocharged engine, it is necessary to maintain a high speed when going up hills. Do not lug the engine using a low RPM. Instead, select a lower gear in the transmission to increase the speed of the engine.

Engine Speed Limitations It is extremely importance to operate the engine within recommended RPMs. The following chart indicates the maximum recommended speeds depending on driving conditions.

Driving Conditions Speed Normal Speed (cruising) 1400 @ 1600RPM Ascending changes (up-shift) 1600 RPM Descending Changes (down-shift)

1200 RPM

Starting 1. Turn ignition key on but Do NOT depress the accelerator pedal. 2. The engine oil pressure gauge should increase within 5-10 seconds

a) If this does NOT occur, turn the engine off b) Check the engine oil level, fill as needed c) Turn on engine again and check oil pressure. If problem persists, take engine in for servicing.

3. Allow the engine to idle until normal operational temperatures are indicated.

Note Idle speed for this engine is Not Adjustable

Mack E7 Engine 750RPM


4

4. To allow the coolant temperatures to reach optimal operating range, idle the engine for 3-5 minutes before operating at full speed/load capacity.

5. When starting the engine cold, maintain idle speed for 3-5 minutes, or until the coolant temperature reaches 60°C (140°F).

6. To ensure the oil pressure reaches the turbocharger bearings before increasing the load, do not operate above idle until oil pressure is within normal operating range.

Shut Down

NOTE Do not shut off the engine immediately after running the engine at high speed, at full-load, or immediately after prolonged high power operation.

Allow the engine to idle for 3-5 minutes before shutting off the engine. This will allow the turbocharger and engine to cool down and prevent overheating of the components which can shorten the lifespan of the engine. This should also be performed if the engine was running in high heat conditions (engine coolant temperature above 90° F).

What NOT to do 1. Do not coast in neutral. 2. Avoid excessive idling whenever possible. 3. Do not freely accelerate the engine. This could cause severe damage to the turbocharger and air

compressor. 4. Do not use the motor for breaking. 5. Do not force the engine into lower gears that can result in engine over speed. 6. Do not accelerate engine without a load. This could cause severe damage to the turbocharger and

exhaust system. 7. Do not overload the vehicle or the engine. 8. Do not “lug” the motor – i.e. driving in a high gear with engine speed too low. 9. After running the engine hard or for an excessive amount of time, do not shut off the motor

immediately. Maintain the motor idle for a period of 3 to 5 minutes to lower the engine temperature before shutoff.

Start-up Procedure after Extended In-operation When starting an engine that has not been operated for more than 60 days:

1. Check all engine fluid levels before starting. 2. Engine oil pressure should be indicated on the gauge within 10 seconds after starting. If oil

pressure does NOT register within 10 seconds after starting, shut off engine immediately. 3. Check for any fluid leaks. 4. Allow engine to idle engine for 3 to 5 minutes before operating under load.

Inspection The vehicle should be inspected and serviced by Omnitek trained technicians on a regular basis. Consult your warranty policy for maintenance periods, as well as the areas to be checked. For short-distance runs with frequent starts and shutoffs, the number of operating hours is more important than running mileage.


5

Maintenance NOTE: Do not alter the fuel and ignition system components. The motor is under manufacturers’

warranty and altering of any fuel and ignition system components by unauthorized personnel will automatically void the warranty.

See maintenance schedule on page 8 for all service guide requirements. Use only Omnitek supplied or recommended service parts.

Lubricant & Grade 1. Omnitek CNG Engines must be operated using high-quality premium engine oil especially

formulated for natural gas engines. 2. Synthetic oil may only be used in very cold weather, provided they meet performance and

chemical requirements. Only recommended for use in ambient temperatures consistently below -13°F (-25°C) for improved engine cranking and flow ability. Synthetic oil should NOT BE USED to extend oil drain intervals.

3. Special break-in oil should not be used. 4. Supplemental oil additives such as friction-reducers should not be used unless the oil supplier can

provide evidence of satisfactory performance and has established that the oil has performed satisfactorily in Omnitek engines.

5. An oil analysis can be used as a method to extend drain intervals. Different driving patterns and idle time are the basis of the recommendation.

CAUTION Do not mix different brands of engine oils.

Oil Viscosity Identification

It is highly recommended that Omnitek brand engine oil be used to prolong the service life of the engine. However, if a substitution becomes absolutely necessary, selection of engine oil with appropriate viscosity should be based on engine load and ambient temperature. Natural Gas Engine Oil, Viscosity Identification 15W/40, 20W/40, 25W/40, 20W/50 Natural Gas Engine Oils with Sulfated Ash, wt <0.5% and TBN wt >5% are recommended.

Oil Change Interval Oil Change interval is decided by engine application, ambient condition and oil quality. Replace oil filter at EVERY oil drain interval. Severe operating conditions will require additional oil changes. Normal on-highway use of vehicle 10,000 miles, 6 months, 300 hours

Oil Filling Volume Make sure that the lube oil level inside the oil pan is between the min. and max. markings on the engine oil dipstick.


6

Oil Consumption Engine oil consumption is affected by engine application, ambient condition, oil viscosity and oil quality. Low-grade engine oil will increase oil consumption. Furthermore, as oil ages, engine oil consumption will increase.

Coolant 1. Check coolant level before every trip. 2. Check concentration level every 30,000 miles/6 months. 3. Drain/flush cooling system every 60,000 miles/2 years. Refill with a mix of water and antifreeze.

Always use antifreeze. In addition to freeze protection, antifreeze is essential for overheating and corrosion protection. The primary purpose of antifreeze is to lower the freeze point of the coolant. Additional performance characteristics of coolants that are affected by the use of antifreeze include boiling point, corrosion protection and vapor pressure. A 40/60 mixture of antifreeze and water provides optimum boiling point and freeze point protection for engines.

Adjusting the Valve Clearance Valve clearance affects the performance of the natural gas engine. If valve clearance is not to specification, engine power can be lower and fuel consumption may be increased.

Clearance - COLD Intake .50mm (.020”) 20 ft lb torque on valve adjust screw nut Exhaust .76mm (.030”) Adjust valves every: 60,000 miles

Ignition Timing:

Not Adjustable - Idle 15 Degrees BTDC

Spark Plugs Spark plug durability depends on engine application and spark plug type. Premium precious metal and multi-electrode spark plugs will last longer. Omnitek does not recommend Platinum spark plugs for all applications. Certain components could be present in the gas, which adversely affect the durability of Platinum. It is highly recommended that Omnitek brand pre-gapped Iridium/Yttrium spark plugs be used when servicing the engine. However, if a substitution becomes absolutely necessary, selection of spark plugs with the appropriate electrode gap is necessary.

Electrode Gap 0.35 mm (0.014”)

Spark Plug Change Interval

Omnitek Premium Spark Plugs 40,000 miles Conventional Spark Plugs 6,000 miles


7

Maintenance Schedule

Daily

Weekly

First Service - 50 Hrs or 2000 miles

Every 300 hrs / 10,000 miles / 6 month

Every 600 hrs / 20,000 miles / 6 month

Every 1,000 hrs / 40,000 miles / 12 month

Every 3,000 hrs / 120,000 miles / 24 month

X Check Coolant Level - add as required

X Check Engine Oil Level - add as required 1

X Check Engine for Coolant & Oil leaks

X Check Air Intake Restriction Indicator

X Listen for unusual engine noise

X X Check Low-Pressure Gas System for leaks and wear on hose

X X Check High-Pressure Gas System for leaks

X X Adjust Valves

X X Tighten Turbocharger and Exhaust Manifold Bolts

X X Check operation of Turbocharger and Wastegate

X X Change Engine Oil 1,2

X X Change Engine Oil Filter

X Drain High-Pressure Gas Filter

X Inspect Catalytic Converter and Exhaust System

X Inspect High-Pressure Natural Gas Tanks & Lines

X Pressure test Cooling System

X Service Battery & check Charging System

X Check Belts for tension & wear

X Inspect Air Filter & replace if required

X Replace High-Pressure Gas Filter Element

X Replace Premium Spark Plugs 3

X Inspect Ignition Wires & Ignition Coils

X Inspect Crankcase Ventilation System, clean/replace as needed

X Replace UEGO Sensor - Front Oxygen Sensor

X Replace HEGO Sensor - Rear Oxygen Sensor

X Replace Ignition Coils

X Replace Ignition Wires

X Flush Cooling System NOTES:

1 ONLY USE OMNITEK RECCOMENDED OIL TYPE

2 SEVERE OPERATING CONDITIONS REQUIRE ADDITIONAL OIL CHANGES

3

NON-OMNITEK PREMIUM SPARK PLUGS MAY REQUIRE AN ACCELERATED REPLACEMENT SCHEDULE


8

ECM System Troubleshooting Guide

1.0 Component Installation 3

2.0 Introduction to Diagnostic Trouble Codes (DTCs) 3

3.0 Troubleshooting Intermittent DTCs 4

4.0 Oxygen Sensor Inversion Phenomenon 4 Basic Function of the Oxygen Sensor 4 Advanced Function of the Oxygen Sensor 4 Presence of Excess Oxygen in Exhaust Stream 4 Sources of Excess Oxygen in the Exhaust Stream 5

5.0 Diagnostic Trouble Codes (DTCs) & Troubleshooting Procedures 6 P0106 Manifold Absolute Air Pressure Sensor (MAP) Performance 7 P0107 Manifold Absolute Air Pressure Sensor (MAP) Low Voltage 7 P0108 Manifold Absolute Air Pressure Sensor (MAP) High Voltage 8 P0112 Intake Air Temperature Sensor (IATS) Circuit Low Voltage 9 P0113 Intake Air Temperature Sensor (IATS) Circuit High Voltage 10 P0117 Engine Coolant Temperature Sensor (ECTS) Circuit Low Voltage 11 P0118 Engine Coolant Temperature Sensor (ECTS) Circuit High Voltage 12 P0125 Insufficient Engine Coolant Temperature for Closed Loop Mode 13 P0128 Coolant Thermostat Performance 13 P0131 Oxygen Sensor Circuit Low Voltage (Bank 1, Sensor 1) 13 P0132 Oxygen Sensor Circuit High Voltage (Bank 1, Sensor 1) 14 P0133 Oxygen Sensor Circuit Slow Response (Bank 1, Sensor 1) 15 P0134 Oxygen Sensor Circuit No Activity Detected (Bank 1, Sensor 1) 16 P0151 Oxygen Sensor Circuit Low Voltage (Bank 2, Sensor 1) 17 P0152 Oxygen Sensor Circuit High Voltage (Bank 2, Sensor 1) 18 P0153 Oxygen Sensor Circuit Slow Response (Bank 2, Sensor 1) 19 P0154 Oxygen Sensor Circuit No Activity Detected (Bank 2, Sensor 1) 20 P0171 Fuel Trim Too Lean – Bank 1 21 P0172 Fuel Trim Too Rich – Bank 1 22 P0174 Fuel Trim Too Lean – Bank 2 23 P0172 Fuel Trim Too Rich – Bank 1 24 P0175 Fuel Trim Too Rich – Bank 2 25 P0182 Fuel Temperature Sensor (FTS) Circuit Low Voltage 26 P0183 Fuel Temperature Sensor (FTS) Circuit High Voltage 27 P0217 Engine Coolant Temperature (ECT) Over Temperature Condition 28 P0219 Engine Over-Speed Condition 28 P0335 Crankshaft Position Sensor Fault 28 P0462 CNG Storage Pressure Circuit Low Voltage 29 P0463 CNG Storage Pressure Circuit High Voltage 30 P0502 Vehicle Speed Sensor Fault 30 P0521 Oil Pressure Sensor Performance 31 P0522 Oil Pressure Sensor Circuit Low Voltage 32 P0523 Oil Pressure Sensor Circuit High Voltage 33 P0524 Low Oil Pressure for Engine Operation 34 P0562 System Voltage Low 34 P0563 System Voltage High 34 P0601 Checksum Error 34 P0602 Programming Error 34 P0603 Keep-Alive Memory Error 35 P1105 Manifold Absolute Air Pressure (MAP) Sensor Signal – No Change Detected 36 P1106 Manifold Absolute Air Pressure (MAP) Slow Change After Crank 36 P1107 No Manifold Absolute Air Pressure (MAP) Change with Engine Stall 36

ECM System Troubleshooting Guide Page 1 of 57

P1133 UEGO Sensor Circuit Slow Response (Bank 1, Sensor 1) 36 P1134 UEGO Sensor Circuit No Activity Detected (Bank 1, Sensor 1) 36 P1135 UEGO Sensor Calibration Error (Bank 1, Sensor 1) 37 P1136 UEGO Sensor Pump Circuit Fault (Bank 1, Sensor 1) 38 P1137 UEGO Sensor Reference Fault (Bank 1, Sensor 1) 39 P1138 UEGO Sensor Heater Overheat (Bank 1, Sensor 1) 40 P1139 UEGO Sensor Temperature Sense Cycle Fault (Bank 1, Sensor 1) 41 P1231 CNG Leak Detected 41 P1222 Throttle Position Sensor (TPS) Circuit Low Voltage 42 P1223 Throttle Position Sensor (TPS) Circuit High Voltage 43 P1224 Throttle Position Sensor (TPS) Circuit Intermittent 44 P1244 Wastegate Over-boost 45 P1245 Wastegate Performance 45 P1246 Wastegate Oscillating 45 P1272 Accelerator 1 Pedal Position (APP1) Circuit Low Voltage 46 P1273 Accelerator 1 Pedal Position (APP1) Circuit High Voltage 47 P1274 Accelerator 1 Pedal Position (APP1) Intermittent 48 P1276 Accelerator 2 Pedal Position (APP2) Circuit Low Voltage 49 P1277 Accelerator 2 Pedal Position (APP2) Circuit High Voltage 50 P1278 Accelerator 2 Pedal Position (APP2) Intermittent 51 P1335 Crankshaft or Camshaft Position Sensor Circuit Malfunction 52 P1350 Ignition Coil Primary/Secondary Circuit Malfunction 53 P1351 Ignition Coil Secondary Circuit Malfunction 53 P1352 Ignition Timing Circuit Malfunction 53 P1501 No Vehicle Acceleration with High Throttle 53 P1502 High RPM at Very Light Load 53 P1506 Idle Air Controller (IAC) Low Airflow 53 P1507 Idle Air Controller (IAC) High Airflow 53 P1514 Throttle Flow Error 54 P1515 Throttle Flow Error at Idle 54 P1560 Injector Power Relay Stuck Shorted 55 P1561 Injector Power Relay Stuck Open 56 P1606 Incompatible Calibration File 57 P1609 Programmed Feature Not Compatible with Hardware 57


The following are some useful and highly effective tests or checks that can be done to help troubleshoot a vehicle without the use of a laptop or scan tool. Try these first when beginning to troubleshoot an issue.

Wiring & Fuses

Perform a visual check for proper electrical grounding, wiring condition, and to ensure all sensors are properly connected. Check fuses if it is suspected that one may be faulty.

Leaks

CNG leaks are a safety issue and can cause a number of problems including; a poorly running engine, difficult starts, and poor fuel economy. Check for leaks at all CNG supply connections between the Regulator and Injection Block. Checks should include the fittings, filters, valves, clamps and supply hoses.

Further checks for leaks should include the Injector Block assembly, the Fuel Injectors, and both inlet and outlet hose connections.

If a set of injectors is found to be leaking they should be replaced. File the appropriate RMA form and return the faulty injectors. Do not try to clean them.

Shut-Off Valves

An improperly installed or maintained shut-off valve can lead to operational problems. Suspected insufficient CNG flow may be the result of an improperly functioning valve. Ensure the valve is connected and the valve inside moves freely and is free from any debris.

Vacuum Leaks

Perform a quick visual inspection to ensure hoses are not damaged or that connections have not come off.

1.0 Component Installation

If a failed component has been identified, refer to the corresponding Installation Manual section for proper component removal and installation instructions.

Note: Failed regulators, injectors and ECMs are not field serviceable and are to be returned along with completed RMA forms.

2.0 Introduction to Diagnostic Trouble Codes (DTCs)

Each diagnostic trouble code is based on a diagnostic test. A diagnostic test examines information from sensors and devices and compares the information to a set of rules on how the sensors and devices should be acting. If the information from the sensors and devices do not meet the criteria set forth in the rules, then it sets a trouble code and records any relevant information to help diagnose the problem in a snapshot.

There are two types of diagnostic tests:

1. Non-intrusive diagnostic tests are run mostly in the background while the engine is running. Several other tests are run while the engine is not running such as test P1107 which checks for a change in the MAP signal as the engine is turned off.

2. Intrusive tests temporarily change engine operation parameters to check for proper responses from sensors. An example would be P0420 which shifts the air/fuel ratio to rich, then to lean, then back to rich again to test catalyst responses.

Most DTC tests are run during each code loop. A code loop equals one cycle through the ECM firmware code. Many of the codes are not run until the engine has reached a preset operating temperature.

This section provides information on how each DTC is set and how to troubleshoot it.


3.0 Troubleshooting Intermittent DTCs

Intermittent diagnostic trouble codes are the most difficult to trace. Because the problem usually appears under unknown conditions, the source of the problem typically cannot be found in the normal manner. The following procedures outline the recommended practices for finding the cause(s) of an intermittent DTC:

1) Perform a thorough visual and physical check of electrical wiring, connectors and component condition. Pay special attention to:

a) ECM grounding points: Include location, cleanliness and proper fastener torque.

b) Wiring connections: Ensure all sensors and devices are connected properly, and connector terminals have not spread or corroded in a manner which may inhibit conduction.

c) Wire condition: Ensure there are no pinches, kinks or cuts in the wire.

d) Wire routing: Ensure wire is not in close proximity to high-tension ignition leads, exhaust manifolds and pipes, belts, pulleys, gears or the engine cooling fan.

2) Perform a road test using the logging tool in OmniWatch to log data related to the DTC. Watch the viewer screen for evidence of the malfunction. Any data collected in the snapshot which indicates the conditions under which the DTC was set may be useful in recreating and confirming the DTC.

4.0 Oxygen Sensor Inversion Phenomenon

Oxygen Sensor Inversion is the most commonly misdiagnosed engine management malfunction. Due to the wide range of symptoms and equally wide range of causes, Oxygen Sensor Inversion results in many unnecessary high cost parts replacements, warranty claims and diagnosis time.

Oxygen Sensor Inversion is the misinterpretation of an Oxygen Sensor signal by an Engine Control System. Common symptoms include engine misfire, high fuel consumption, low power, overheating, catalyst damage and engine damage. This condition can occur in all closed-loop natural gas conversions and is difficult to diagnose as it can have any number of symptoms which are not specific to Oxygen Sensor Inversion.

Basic Function of the Oxygen Sensor

The Oxygen Sensor produces a voltage based on the oxygen content of the exhaust stream. If there is excess oxygen in the exhaust stream, the oxygen sensor will produce a voltage of about 0.1v. If there is no excess oxygen in the exhaust stream, the Oxygen Sensor will produce a voltage of about 0.8v, as shown in Figure 4-1 & Figure 4-2.

Advanced Function of the Oxygen Sensor

While the ECM controls fuelling based on the Oxygen Sensor signal, it does not attempt to supply a constant stoichiometric mixture. Instead, the ECM oscillates the air/fuel ratio up and down to within about 6% of stoichiometric (lean and rich). The Oxygen Sensor produces a sinusoidal waveform following the lean-rich fluctuations as shown in Figure 4-3. This allows the catalyst to retain the oxygen generated by the reduction of nitrogen oxides (NOx) in the rich periods and use it to convert carbon monoxide (CO) and hydrocarbons into carbon dioxide (CO2) and water in the lean periods. Both reactions take place simultaneously but by changing the air/fuel ratio, catalyst efficiency is maximized.

Presence of Excess Oxygen in Exhaust Stream

In the event excess oxygen is present in the exhaust stream, the Oxygen Sensor will detect the oxygen and the ECM will allow for the supply of more fuel to the engine, even if it is in a stoichiometric or rich state. Because of the narrow flammability limit of natural gas, the system can soon become too rich for proper combustion, causing one or more cylinders to misfire. Cylinder misfire in turn introduces another source of oxygen in the exhaust. This perpetual cycle is called “Oxygen Sensor Inversion” where the ECM gets fooled into thinking the engine is lean when it is actually rich or stoichiometric.


Figure 4-3 illustrates a typical Oxygen Sensor response during stoichiometric operation while Figure 4-4 shows the result of an exhaust leak or misfire on the oxygen sensor signal. This signal indicates that the engine is generally running in a lean state even if the ECM is delivering an appropriate amount of fuel. When Oxygen Sensor Inversion occurs, carbon monoxide and hydrocarbon emissions are significantly higher than normal operation. Normal engine-out oxygen concentrations are between 0.2% and 2%. Anything higher indicates a misfire or an exhaust leak which both can cause Oxygen Sensor Inversion.

Sources of Excess Oxygen in the Exhaust Stream

Diagnosis of Oxygen Sensor Inversion can be difficult. Excessive oxygen in the exhaust stream can be caused by exhaust leaks and cylinder misfire.

Exhaust leaks allow air to enter the exhaust stream and dilute the exhaust. This increases the oxygen presence in the exhaust stream without affecting the combustion process. If an exhaust leak is present before or near to the Oxygen Sensor location, this may initiate Oxygen Sensor Inversion.

Cylinder misfire, including incomplete combustion, allows the unburned air/fuel mixture to exit through the exhaust. The Oxygen Sensor sees this oxygen and the ECM assumes lean operation regardless of whether the mixture was stoichiometric or rich when it entered the combustion chamber. See Table 4-1 for a list of potential causes of cylinder misfire.

To reduce the effects of Oxygen Sensor Inversion a maximum fuel trim limit is specified in the calibration file. This prevents the ECM from increasing fuel perpetually, thus preventing extreme Oxygen Sensor Inversion and allowing the vehicle to “limp home” for repair. This is not a cure for Oxygen Sensor Inversion, only a limit to minimize its effects on the engine and its operation.

Warning: Do not operate the engine with any misfires present.

Immediately shut off the engine if a misfire develops.

An engine misfire condition will severely damage the catalytic converter.

Figure 4-1:

Oxygeexhaus

n Sensor sees excess oxygen in the t stream.

ECM interprets lean operation and adjusts fuaccordingly.

el

Normal Combustion Interpretation: Lean

Figure 4-2:

Oxygen Sensor sees a lack of oxygen in the eam. exhaust str

ECM interprets rich operation and adjusts fuel accordingly.

Normal Combustion Interpretation: Rich

Normal Combustion iometric Interpretation: Stoich

Figure 4-3:

lean

.

Oxygen Sensor detects flipping betweenand rich.

ECM interprets as stoichiometric operation



des (DTC es

of each ey cover oaches alo

gether to form a possible chain of events leading up to a fault, nd be able to locate the root of that fault. Pay attention to how the engine is operating. Listen and look r signs of abnormal operation and use these symptoms in your diagnosis. Follow proper repair

rocedures to prevent the fault from reoccurring.

able 5-1: Potential causes of cylinder misfire

exhaust leaks

improper timing

poor electrical grounding

poor fuel/air mixing

vacuum leaks

poor cylinder compression

malfunctioning Oxygen Sensor

improper ignition wire connections

improper calibration file

improper spark plug gap

degraded spark plug wires

poor spark plug condition

injector malfunction

poor fuel quality

excessive exhaust backpressure

5.0 Diagnostic Trouble Co s) & Troubleshooting Procedur

The following section gives descriptionsthe most efficient troubleshooting appr

DTC and their troubleshooting procedures. Thng with the most common sources of faults. A good

technician must be able to link symptoms toafop

T

Figure 4-4:

Oxygen Sensor detecoxygen in exhaust stre

ts bias towards excess am.

ration and adjusts fuel ECM interprets lean opeca cordingly.

Misfire with Oxygen Sensor Inversion Interpretation: Lean

P0106 Manifold Absolute Air Pressure Sensor (MAP) Performance

Conditions to set code: This code will set if the ECM detects high load with a low Throttle Position Sensor (TPS) signal during the first 2 minutes of starting the engine. It will not set if a TPS trouble code has previously been set.

Troubleshooting procedure: Note that while the engine is off, the MAP voltage will depend on your altitude and current barometric pressure. A 4.5v signal from the MAP Sensor is interpreted as a pressure of 14.5psi and 0v is interpreted as 1.45psi. All pressures are absolute.

Troubleshooting procedure: Step Action Value Yes No

1 Are there any trouble codes set? --

Diagnose other codes first, and then return to this one.

Go to step 2.

2

Check MAP Sensor hose for cracks, breaks or leaks.

Any found?

-- Repair or replace hose and re-check operation.

Go to step 3.

3

a) Turn ignition key off. b) Connect a PC to a Datalink and the engine. c) Start OmniWatch. d) Start the engine. e) Check MAP voltage.

> 4v

The fault is in the wiring. Check for a short between 5v reference and MAP signal wires.

Fault is intermittent. See troubleshooting intermittent DTCs.

P0107 Manifold Absolute Air Pressure Sensor (MAP) Low Voltage

Conditions to set code: This code will set if VMAP < .01v for 1.5 seconds.

Actions taken by ECM: The ECM substitutes a modified Throttle Position Sensor (TPS) value for the MAP value. If both TPS and MAP codes are set, then it just substitutes 7.25psi for the MAP value.


1

a) Turn ignition key off. b) Connect a PC to a Datalink and engine. c) Start OmniWatch. d) Turn ignition key ON, DO NOT START engine. e) Check MAP voltage.

< .01v Go to step 2.


2

a) Disconnect the MAP Sensor electrical connector. b) Install a jumper between the MAP signal wire and 5v reference. c) Check MAP voltage.

5v

Problem is sensor or connection at sensor. Repair or replace and confirm operation.

Fault is in 5v supply to MAP sensor. Check wiring for open circuit. Repair and check operation.


P0108 Manifold Absolute Air Pressure Sensor (MAP) High Voltage

Conditions to set code: There are two engine speed conditions under which this code will set:

1) If engine speed is < 500 rpm and the Throttle Position Sensor (TPS) value is < 5% and VMAP > 4.9v for 2.5 seconds.

2) If engine speed is > 500 rpm and the TPS value is < 20% and VMAP > 4.9v for 5 seconds.

This code will not set if a TPS trouble code has already been set.

Actions taken by ECM: The ECM substitutes a modified TPS value for the MAP value. If a TPS code has previously been set, this code will not set. If a MAP code sets a TPS code, the ECM substitutes 7.25psi for the MAP value.

Troubleshooting procedure: Note that while the engine is off, the MAP voltage will depend on your altitude and current barometric pressure. A 4.5v signal from the MAP Sensor is interpreted as a pressure of 14.5psi and 0v is interpreted as 1.5psi. All pressures are absolute.


1

a) Turn ignition key off. b) Connect a PC to a Datalink and the engine. c) Start OmniWatch. d) Turn ignition key ON, DO NOT START engine. e) Check MAP voltage.

> your atmospheric value (usually 3.75 – 4.5v)

Go to step 2.


2

a) Disconnect the MAP Sensor electrical connector. b) Install a jumper between the MAP signal wire and ground. c) Check MAP voltage.

< .01v

Problem is sensor or connection at sensor. Repair or replace and confirm operation.

The MAP signal wire is shorted to ground. Check and repair as necessary.


P0112 Intake Air Temperature Sensor (IATS) Circuit Low Voltage

Conditions to set code: This code will set if VIAT < MinVIAT for the time limit. Typically, the MinVIAT is approximately .05v and the time limit is approximately 1 second. These nominal configurations are preset in the calibration file.

Note: High IATS Raw value (voltage) corresponds to a low input temperature and a low IATS Raw value corresponds to a high input temperature. Maximum voltage is 5v at approximately -40°F and minimum voltage is 0v corresponding to a temperature of approximately 302°F.

Actions taken by ECM: If this code is set, the Malfunction Indicator Lamp will illuminate immediately. Once the source of the malfunction is corrected, the lamp will turn off after four warm-up cycles if the code has not been cleared via OmniWatch.

The ECM will substitute a default IAT value until the next key-off cycle. If the malfunction still exists at the next key-on cycle, the ECM will again substitute a default IAT value.

Note: A key-off cycle requires about one minute with the key off before the ECM will clear codes or perform any key-off cycle functions.

Disconnect the IATS.

Does IATS Raw read > 4.95v?

Fault: • Fault is intermittent. Fix: • See Troubleshooting Intermittent DTCs.

Fault: • Sensor signal wire shorted to ground or sensor ground, or the ECM is faulty. Fix: • Check for short and repair as required. If no short is found, replace ECM.

No Yes

No Yes

Do the Following:

1. Turn ignition key off. 2. Connect a PC to a Datalink and the engine. 3. Start OmniWatch. 4. Turn the ignition key ON, DO NOT START engine. The vehicle should be stabilized at or around room temperature (approx. 70°F).

Does IATS Raw read < .05v?

Fault: • Sensor or connection at sensor.

Fix: • Repair or replace and confirm operation.

Troubleshooting Procedure P0112 Intake Air Temperature Sensor Circuit Low Voltage


P0113 Intake Air Temperature Sensor (IATS) Circuit High Voltage

Conditions to set code: This code will set if VIAT > MaxVIAT for the time limit. These nominal configurations are preset in the calibration file.

Note: High IATS Raw value (voltage) corresponds to a low input temperature and a low IATS Raw value corresponds to a high input temperature. Maximum voltage is 5v at approximately -40°F and minimum voltage is 0v corresponding to a temperature of approximately 302°F.

This code can be set if the vehicle is operating in extremely cold temperatures (-22 to -40°F). If this is the case, the code can be cleared and operation can resume.


The ECM will substitute a default IAT value until the next key-off cycle. If the malfunction still exists at the next key-on cycle, the ECM will again substitute a default IAT value.


Fault: • Fault is intermittent.

Fix: • See Troubleshooting Intermittent DTCs.

• Disconnect the IATS. • Insert a jumper between terminals A & B on the IATS Harness Connector.


Fault: • Sensor or connection at sensor. Fix: • Repair or replace and confirm operation.

Jumper the sensor signal wire to an engine ground.


Fault: • Sensor ground circuit is open. Fix: • Check and repair as necessary.

No Yes

No Yes

No Yes

Do the Following:


Does IATS Raw read > 4.95v?

Fault: • Sensor signal circuit is open. Fix: • Check and repair as necessary.

Troubleshooting Procedure P0113 Intake Air Temperature Sensor Circuit High Voltage


P0117 Engine Coolant Temperature Sensor (ECTS) Circuit Low Voltage

Conditions to set code: This code will set if VECT < MinVECT for the time limit. These nominal configurations are preset in the calibration file.

Note: High ECTS Raw value (voltage) corresponds to a low input temperature and a low ECTS Raw value corresponds to a high input temperature. Maximum voltage is 5v at approximately -40°F and minimum voltage is 0v corresponding to a temperature of approximately 302°F.


The ECM will substitute a default ECT value until the next key-off cycle. If the malfunction still exists at the next key-on cycle, the ECM will again substitute a default ECT value.



Disconnect the ECTS. Does ECTS Raw read > 4.95v?

Fault: • Sensor signal wire shorted to ground or sensor ground, or ECM is faulty. Fix: • Check for short and repair as required. If no short is found, replace ECM.

No Yes

No Yes

Do the Following:


Does ECTS Raw read < .05v?



Troubleshooting Procedure P0117 Engine Coolant Temperature Sensor Circuit Low Voltage


P0118 Engine Coolant Temperature Sensor (ECTS) Circuit High Voltage

Conditions to set code: This code will set if VECT > MaxVECT for the time limit. These nominal configurations are preset in the calibration file.

Note: High ECTS Raw value (voltage) corresponds to a low input temperature and a low ECTS Raw value corresponds to a high input temperature. Maximum voltage is 5v at approximately -40°F and minimum voltage is 0v corresponding to a temperature of approximately 302°F. This code can be set if the vehicle is operating in extremely cold temperatures (-22 to -40°F). If this is the case, the code can be cleared and operation can resume.


The ECM will substitute a default ECT value until the next key-off cycle. If the malfunction still exists at the next key-on cycle, the ECM will again substitute a default ECT value.



• Disconnect the ECTS. • Insert a jumper between terminals A & B on the ECTS Harness Connector.



Jumper the sensor signal wire to an engine ground.



No Yes

No Yes

No Yes


Do the Following:


Does ECTS Raw read > 4.95v?

Troubleshooting Procedure P0118 Engine Coolant Temperature Sensor Circuit High Voltage


P0125 Insufficient Engine Coolant Temperature for Closed Loop Mode

Conditions to set code: This code will set if the ECT is < 140°F for 30 minutes.

Troubleshooting: A malfunctioning thermostat primarily causes this code.

P0128 Coolant Thermostat Performance

Conditions to set code: This code will set if the ECT is < 140°F for 10 to 30 minutes. The time taken to set the code will depend on the coolant temperature at start-up, i.e. if it is -22°F it will take longer than if it is 122°F.

Troubleshooting: A malfunctioning thermostat primarily causes this code.

P0131 Oxygen Sensor Circuit Low Voltage (Bank 1, Sensor 1)

Conditions to set code: This code will set if the output of the Oxygen Sensor (Bank 1, Sensor 1) drops below .33v for more than 50 seconds.

Actions taken by ECM: The ECM will go into open-loop operation and disable fuel trimming.


1

a) Turn ignition key off. b) Connect a PC to a Datalink and the engine. c) Start OmniWatch. d) Start the engine. e) Run the engine until it reaches proper operating temperature. f) Check Oxygen Sensor voltage.



2 a) Disconnect the Oxygen Sensor electrical connector. b) Check Oxygen Sensor voltage.

< .33v Go to step 3. Go to step 4.

3

Check the Oxygen Sensor signal wire for a short to ground or sensor ground in the harness. Is there a short?

-- Repair and confirm operation.

ECM is damaged. Replace and confirm operation.

4

Use a multi-meter to check the following pin-outs on the Oxygen Sensor connector (device side):

a) Resistance between terminal A & C; b) Resistance between terminal B & C.

< 100Ω

Sensor is shorted. Replace and confirm operation.

Exhaust leak before the Oxygen Sensor. Repair and confirm operation.


P0132 Oxygen Sensor Circuit High Voltage (Bank 1, Sensor 1)

Conditions to set code: This code will set if the output of the Oxygen Sensor (Bank 1, Sensor 1) rises above .7v for more than 50 seconds.

Actions Taken By ECM: The ECM will go into open-loop operation and disable fuel trimming.


1


> .5v Go to step 2.



> .5v Go to step 3.

Sensor or connection at sensor is at fault. Repair or replace as necessary and confirm operation.

3

Check the Oxygen Sensor signal wire for a short to power in the harness.

Is there a short?




P0133 Oxygen Sensor Circuit Slow Response (Bank 1, Sensor 1)

Conditions to set Code: This code will set if the Oxygen Sensor voltage switch rate (bank 1, sensor 1) is below the calibrated limit AND the voltage is hovering in the middle of its range. The ECM will not check for this code; during the first 250 seconds after start-up, MAP must be above 3psi, and engine speed must be above 1000rpm.

Actions Taken by ECM: The ECM will go into open-loop operation and disable fuel trimming.


1

a) Turn ignition key off. b) Connect a PC to a Datalink and the engine. c) Start OmniWatch. d) Start the engine. e) Listen and feel for exhaust leaks from all exhaust flanges, welds and clamped joints.

Are there any leaks?

--

Repair leak and confirm proper Oxygen Sensor operation.

Go to step 2.

2

Inspect sensor and wiring harness for shorts.

Are there any shorts?

-- Repair wiring as necessary.

Oxygen Sensor has aged past its effective life or been contaminated by silicone or burning oil. Replace the sensor and check the engine for burning oil or foreign contaminates in the intake or exhaust system.


P0134 Oxygen Sensor Circuit No Activity Detected (Bank 1, Sensor 1)

Conditions to set Code: This code will set if the Oxygen Sensor voltage (bank 1, sensor 1) does not cross the threshold voltage band of .35v to .68v for 60 seconds. The ECM will not check for this code during the first 250 seconds after start-up or if the Oxygen Sensor is below 199°F.



1

a) Turn ignition key off. b) Connect a PC to a Datalink and the engine. c) Start OmniWatch. d) Turn ignition key ON, DO NOT START engine. e) The Oxygen Sensor should slowly warm to the touch (it takes about 10 minutes to warm).

Does it?

--

There is an exhaust leak. Locate and repair the leak. Confirm proper Oxygen Sensor operation.

Go to step 2.

2

Inspect sensor and wiring harness for open circuits.

Any found?


Oxygen Sensor has been contaminated. Replace and check the engine for burning oil or foreign contaminates in the intake or exhaust system.


P0151 Oxygen Sensor Circuit Low Voltage (Bank 2, Sensor 1)

Conditions to set code: This code will set if the output of the Oxygen Sensor (Bank 2, Sensor 1) drops below .33v for more than 50 seconds.



1





< .33v Go to step 3. Go to step 4.

3

Check the Oxygen Sensor signal wire for a short to ground or sensor ground in the harness.

Is there a short?



4

Use a multi-meter to check the following pin-outs on the Oxygen Sensor connector (device side):

a) Resistance between terminal A & C; b) Resistance between terminal B & C.

< 100Ω

Sensor is shorted. Replace and confirm operation.

Exhaust leak before the Oxygen Sensor. Repair and confirm operation.


P0152 Oxygen Sensor Circuit High Voltage (Bank 2, Sensor 1)

Conditions to set Code: This code will set if the output of the Oxygen Sensor (Bank 2, Sensor 1) rises above .7v for more than 50 seconds.



1


> .5v Go to step 2.



> .5v Go to step 3.

Sensor or connection at sensor is at fault. Repair or replace as necessary and confirm operation.

3

Check the Oxygen Sensor signal wire for a short to power in the harness.

Is there a short?




P0153 Oxygen Sensor Circuit Slow Response (Bank 2, Sensor 1)

Conditions to set Code: This code will set if the Oxygen Sensor voltage switch rate (bank 2, sensor 1) is below the calibrated limit AND the voltage is hovering in the middle of its range. The ECM will not check for this code; during the first 250 seconds after start-up, MAP must be above 3psi, and engine speed must be above 1000 RPM.



1

a) Turn ignition key off. b) Connect a PC to a Datalink and the engine. c) Start OmniWatch. d) Start the engine. e) Listen and feel for exhaust leaks from all exhaust flanges, welds and clamped joints.

Are there any leaks?

--

Repair leak and confirm proper Oxygen Sensor operation.

Go to step 2.

2 Inspect sensor and wiring harness for shorts.

Are there any shorts? --

Repair wiring as necessary.

Oxygen Sensor has aged past its effective life or been contaminated by silicone or burning oil. Replace the sensor and check the engine for burning oil or foreign contaminates in the intake or exhaust system.


P0154 Oxygen Sensor Circuit No Activity Detected (Bank 2, Sensor 1)

Conditions to set Code: This code will set if the Oxygen Sensor voltage (bank 2, sensor 1) does not cross the threshold voltage band of .35v to .68v for 60 seconds. The ECM will not check for this code during the first 250 seconds after start-up or if the Oxygen Sensor is below 199°F.



1

a) Turn ignition key off. b) Connect a PC to a Datalink and the engine. c) Start OmniWatch. d) Turn ignition key ON, DO NOT START engine. e) The Oxygen Sensor should slowly warm to the touch (it takes about 10 minutes to warm).

Does it?

--

There is an exhaust leak. Locate and repair the leak. Confirm proper Oxygen Sensor operation.

Go to step 2.

2

Inspect sensor and wiring harness for open circuits.

Any found?


Oxygen Sensor has been contaminated. Replace and check the engine for burning oil or foreign contaminates in the intake or exhaust system.


P0171 Fuel Trim Too Lean – Bank 1

Conditions to set Code: On systems with UEGO Sensors, this DTC indicates that the total fuel trim correction is higher than a calibrated value if the maximum number of out-of-range block-learn-cells learns values at or above the maximum fuel trim value. These nominal configurations are preset in the calibration file.

This code indicates general system errors not specific component errors. Troubleshooting will require knowledge, understanding and experience with engines and fuel injection systems.

This code can often be set in conjunction with other codes which may point toward the root of the problem. Check for other DTCs.

Are there any other DTCs set?

No Yes

Check and clear those codes first. If this code reappears after the others have been cleared, then return to this troubleshooting procedure.

Do the Following:

The vehicle should be stabilized at or around room temperature (approx. 70°F). 1. Turn ignition key off. 2. Connect a PC to a Datalink and the engine. 3. Start OmniWatch. 4. Install a pressure gauge in the Regulator outlet line. 5. Start the engine. The pressure gauge at engine idle should read within 10% of the specified Regulator outlet pressure shown on the viewer screen of OmniWatch.

Does it?

No Yes

Check Exhaust for: • Leaks, cracks, corrosion and faulty gaskets. • Proper Oxygen Sensor installation. • Fouled or contaminated Oxygen Sensor.

Check Intake for: • Broken or disconnected vacuum hoses, PCV hoses, and EGR lines.

Check CNG Delivery system for: • Fouled, sticky or clogged injectors. • Plugged mixing device. • Leaking gas delivery hoses and broken or improperly installed fittings.

Check the Following: • Ensure cylinder valves are fully open. • Check all filter elements (both coalescing and particulate filters). • Check high pressure lines for restriction.

Was the problem found?

Fault: • Regulator malfunctioning. Fix: • Replace Regulator and confirm proper operation.

No Yes

Troubleshooting Procedures P0171 Fuel Trim Too Lean – Bank 1

Repair problems as found and confirm proper operation.


P0172 Fuel Trim Too Rich – Bank 1

Conditions to set Code: On systems with UEGO Sensors, this DTC indicates that the total fuel trim correction is higher than a calibrated value if the maximum number of out-of-range block-learn-cells learns values at or below the minimum fuel trim value. These nominal configurations are preset in the calibration file.


No Yes

No Yes

Check Intake for: • Restriction. • Plugged air filter. • Disconnected MAP Sensor line.

Check CNG Delivery system for: • Fouled or sticky CNG injectors. • Misaligned mixing device. • Damaged injector o-rings.

Check Exhaust for: • Restriction in tailpipe or catalyst. • Contaminated Oxygen Sensor.

Fault: • Regulator malfunctioning. Fix: • Replace Regulator and confirm proper operation.


Do the Following:

The vehicle should be stabilized at or around room temperature (approx. 70°F). 1. Turn ignition key off. 2. Connect a PC to a Datalink and the engine. 3. Start OmniWatch. 4. Install a pressure gauge in the Regulator outlet line. 5. Start the engine. The pressure gauge at engine idle should read within 10% of the specified Regulator outlet pressure shown on the viewer screen of OmniWatch.

Does it?



Troubleshooting Procedure P0172 Fuel Trim Too Rich – Bank 1


P0174 Fuel Trim Too Lean – Bank 2

Conditions to set Code: This code will set if the fuel trim is < .78 for 10 seconds.



1



--


Go to step 2.

2

a) Turn ignition key off. b) Connect a PC to a Datalink and the engine. c) Start OmniWatch. d) Install a pressure gauge in the regulator outlet line. e) Start the engine. The pressure gauge at engine idle should read within 10% of the specified Regulator outlet pressure shown on the viewer screen of OmniWatch.

Does it?

-- Go to step 3. Go to step 4.

3

a) Inspect for exhaust leaks, proper Oxygen Sensor installation or a fouled or contaminated Oxygen Sensor. b) Inspect the intake for broken or disconnected vacuum hoses, PCV hoses, and EGR lines. c) Check the CNG delivery system for fouled or clogged injectors, plugged mixing devices, or leaking gas delivery hoses.

--

4

a) Check to ensure all cylinder valves are fully open. b) Check all filter elements for clogging. c) Check high pressure lines for restriction.

Was the problem found?

-- Repair problems as found and confirm proper operation.

Replace Regulator and confirm proper operation.



Conditions to set Code: This code will set if the fuel trim is > 1.56 for 10 seconds.



1



--


Go to step 2.

2


Does it?

-- Go to step 3. Replace Regulator and confirm proper operation.

3

a) Inspect exhaust for leaks, proper Oxygen Sensor installation or a fouled or contaminated Oxygen Sensor. b) Inspect the intake for broken or disconnected vacuum hoses, PCV hoses and EGR lines. c) Check the CNG delivery system for fouled or clogged injectors, plugged mixing devices, or leaking gas delivery hoses.

--


P0182 Fuel Temperature Sensor (FTS) Circuit Low Voltage

Conditions to Set Code: This code is triggered if the Fuel Temperature Sensor (FTS) voltage drops below its calibrated minimum value of approximately .05v for the maximum low voltage time of about 1 second.

Note: High FTS Raw value (voltage) corresponds to a low input temperature and a low FTS Raw value corresponds to a high input temperature. Maximum voltage is 5v at approximately -40°F and minimum voltage is 0v corresponding to a temperature of approximately 302°F.

Actions Taken By ECM: If this code is set, the Malfunction Indicator Lamp will illuminate immediately. Once the source of the malfunction is corrected, the lamp will turn off after four warm-up cycles if the code has not been cleared via OmniWatch.


Disconnect the FTS.

Does FTS Raw read > 4.95v?

No Yes




No Yes

Fault: • Sensor signal wire shorted to ground or sensor ground, or the ECM is faulty. Fix: • Check for short and repair as required. If no short is found, replace the ECM.

Do the Following:


Does FTS Raw read < .05v?

Troubleshooting Procedures P0182 Fuel Temperature Sensor Circuit Low Voltage


P0183 Fuel Temperature Sensor (FTS) Circuit High Voltage

Conditions to Set Code: This code will set if the Fuel Temperature Sensor (FTS) voltage rises above its calibrated maximum value of approximately 4.97v for the maximum high voltage time of about 1 second.

Note: High FTS Raw value (voltage) corresponds to a low input temperature and a low FTS Raw value corresponds to a high input temperature. Maximum voltage is 5v at approximately -40°F and minimum voltage is 0v corresponding to a temperature of approximately 302°F.

This code can be set if the vehicle is operating in extremely cold temperatures (-22 to -40°F). If this is the case, the code can be cleared and operation can resume.

Actions Taken By ECM: If this code is set, the Malfunction Indicator Lamp will illuminate immediately. Once the source of the malfunction is corrected, the lamp will turn off.

The ECM will substitute a default FTS value until the next key-off cycle. If the malfunction still exists at the next key-on cycle, the ECM will again substitute a default FTS value.


No Yes


• Disconnect the FTS. • Insert a jumper between terminals A & B on the FTS Harness Connector.


No Yes


Jumper the sensor signal wire to the engine.


No Yes



Do the Following:


Does FTS Raw read > 4.95v?

Troubleshooting Procedure P0183 Fuel Temperature Sensor Circuit High Voltage


P0217 Engine Coolant Temperature (ECT) Over Temperature Condition

Conditions to Set Code: This code will set if; the ECT is > 156°F for 10 seconds, the engine has been running for 30 seconds, and there are no other ECT DTCs.

P0219 Engine Over-Speed Condition

Conditions to Set Code: This code will set if the engine speed is > 6000 rpm for 60 seconds cumulative.

P0335 Crankshaft Position Sensor Fault

Conditions to Set Code: This code will set if the ECM is unable to sync with the crankshaft position sensor.

Troubleshooting:

Check the Crankshaft Position Sensor for signs of physical damage.

Check wiring for abrasions or shorts.


P0462 CNG Storage Pressure Circuit Low Voltage

Conditions to Set Code: This code will set if the CNG Storage Pressure Sensor voltage drops below .122v for 5 seconds.


1 Is the CNG cylinder empty? --

Refuel vehicle. Clear the code and check for proper operation.

Go to step 2.

2

a) Turn ignition key off. b) Connect a PC to a Datalink and the engine. c) Start OmniWatch. d) Turn ignition key ON, DO NOT START engine. e) Check CNG cylinder pressure voltage.

<.122v Go to step 3. Fault is intermittent. See Troubleshooting intermittent DTCs.

3

a) Disconnect the Fuel Pressure Sensor electrical connector (or Regulator connector). b) Install a jumper between fuel pressure signal and 5v reference wires on harness. c) Check CNG cylinder pressure voltage.

<.122v Go to step 4.

Fault is in Fuel Pressure Sensor or Regulator wiring. Check and repair or replace as necessary.

4

Inspect vehicle wiring harness for a short between fuel pressure signal wire and ground or sensor ground.

Problem found?

-- Repair as necessary.

Fault is in ECM. Replace and confirm proper operation.


P0463 CNG Storage Pressure Circuit High Voltage

Conditions to Set Code: This code will set if the CNG Storage Pressure Sensor voltage rises above 4.98v for 15 seconds.


1 Is the CNG cylinder full? --

Drive the vehicle until cylinder pressure drops below 2900psi. Then clear the code and check for proper operation.

Go to step 2.

2

a) Turn ignition key off. b) Connect a PC to a Datalink and the engine. c) Start OmniWatch. d) Turn ignition key ON, DO NOT START engine. e) Check CNG cylinder pressure voltage.

<.122v Go to step 3. Fault is intermittent. See Troubleshooting intermittent DTCs.

3

a) Disconnect the Fuel Pressure Sensor electrical connector (or Regulator connector). b) Install a jumper between fuel pressure signal and 5v reference wires on harness. c) Check CNG cylinder pressure voltage.

<.122v Go to step 4.

Fault is in Fuel Pressure Sensor or Regulator wiring. Check and repair or replace as necessary.

4

Inspect vehicle wiring harness for a short between fuel pressure signal wire and ground or sensor ground.

Problem found?

-- Repair as necessary.

Fault is in ECM. Replace and confirm proper operation.

P0502 Vehicle Speed Sensor Fault

Conditions to Set Code: This code will set if the VSS reads 0 mph while MAP is > 7psi and rpm is > 1500.

Troubleshooting:

Check the Crankshaft Position Sensor for signs of physical damage.

Check wiring for abrasions or shorts.


P0521 Oil Pressure Sensor Performance

Conditions to Set Code: This code will set if the Oil Pressure Sensor output does not match the expected oil pressure profile of the engine.

Do the Following:

The vehicle should be stabilized at or around room temperature (approx. 70°F). 1. Turn ignition key off. 2. Connect a PC to a Datalink and the engine. 3. Start OmniWatch. 4. Install a pressure gauge in an oil passage line. 5. Start the engine. The pressure gauge at engine idle should read within 10% of the oil pressure shown on the viewer screen of OmniWatch.

Does it?


Check the following:

• Ensure wiring is intact. • Check pins on Oil Pressure Sensor connector. • Check that the Oil Pressure Sensor has not been replaced with an incorrect one.

Does this fix the problem?

No Yes

No Yes

Repair problems as found and confirm proper operation.

Fault: • Fault is intermittent. Fix: • See Troubleshooting intermittent DTCs.

No Yes

Fault: • Oil Pressure Sensor malfunctioning. Fix: • Replace Oil Pressure Sensor.



Troubleshooting Procedure P0521 Oil Pressure Sensor Performance


P0522 Oil Pressure Sensor Circuit Low Voltage

Conditions to Set Code: This code will set if the Oil Pressure Sensor voltage drops below its calibrated minimum value of approximately .2v for 1 second.

No Yes

Disconnect the sensor.

Does Oil Pressure Raw read < .05v?


No Yes

Fault: • Sensor, connector at sensor, or signal wire in harness is shorted to ground or signal ground. Fix: • Repair or replace and confirm proper operation.

Fault: • Signal wire is shorted to power in the harness. Fix: • Check and repair as necessary.

Do the Following:



Troubleshooting Procedures P0522 Oil Pressure Sensor Low Input


P0523 Oil Pressure Sensor Circuit High Voltage

Conditions to Set Code: This code will be set if the Oil Pressure Sensor voltage rises above the calibrated minimum value of approximately 4.8v for 1 second.

No Yes




No Yes

Fault: • Sensor or connector at sensor. Fix: • Replace or repair and confirm operation.

Fault: • Signal wire is shorted to power in the harness. Fix: • Check and repair as necessary.

Do the Following:


Does Oil Pressure Raw read > 4.95v?

Troubleshooting Procedure P0523 Oil Pressure Sensor High Voltage


P0524 Low Oil Pressure for Engine Operation

Conditions to Set Code:

This code will trigger if the Oil Pressure Sensor voltage drops below its calibrated minimum value of approximately .05v for 1 second.

P0562 System Voltage Low


This code will set if the battery voltage remains at < 6v for 10 seconds.

Troubleshooting:

Check the condition of the battery and alternator. This DTC may occur if either of these is malfunctioning.

P0563 System Voltage High


This code will set if Vsystem > Vmax. Vmax is dependant on the system operating voltage set in the calibration file. If the system voltage is 24v, the maximum voltage is 32.8v. If the system voltage is 12v, the maximum voltage is 18v.

To troubleshoot this code first make sure that you have the correct calibration file installed. This code will set if your 24v vehicle is using the 12v calibration file and vice versa.

Check the vehicle wiring for proper engine block grounds as well as the condition of all battery, starter and alternator electrical connections and cables.

Check the condition of the Battery and Alternator. This DTC may occur if either of these is malfunctioning.

P0601 Checksum Error


This is an internal ROM error. Try reprogramming the firmware. If that fails contact Omnitek technical support.

P0602 Programming Error


This code will set if an error occurs while programming firmware. Try re-programming the firmware. If the problem persists contact Omnitek technical support.


P0603 Keep-Alive Memory Error


This code will set if the ECMs Unkeyed power supply is interrupted a number of times. This number is preset in the calibration file.

Actions Taken By ECM:

The ECM will take no actions apart from setting this code. Poor engine operation will usually result from this condition as block-learn-values are cleared each time the key is cycled. In addition both statistics and DTCs will not be stored.

No Yes

No Yes

Do the Following:

1. Turn the ignition key ON, DO NOT START engine. 2. Remove Unkeyed Power Fuse from fuse holder. 3. Check voltage between the power side of the fuse and ground.

Is there voltage?

No Yes

Fault: • The wire between the Unkeyed Power Fuse and the Unkeyed power source is interrupted.

Fix: • Check wiring and repair as necessary.

Fault: • The Unkeyed Power wire is connected to a Keyed Power source.

Fix: • Check and repair as necessary.

No Yes

No Yes

Fault: • ECM is damaged.

Fix: • Replace ECM and confirm proper operation.

Fault: • Problem is in vehicle wiring.

Fix: • Check and repair as necessary.

Fault: • Wiring is cut or damaged.

Fix: • Repair as necessary.

Do the Following: 1. With the fuse removed, jumper the ECM side of the Unkeyed power fuse holder to the battery. 2. Run the engine until at least one block-learn has set. 3. Turn the ignition key OFF then ON but do not start the engine.

Check the block-learns. Have they been cleared?

Check for interruption in wire between Unkeyed Power fuse holder and the ECM main connector.

Is there a problem with the wiring?

Check for short circuit in wiring and repair as needed. Replace fuse and confirm proper operation.

Do the Following: 1. Turn ignition key off. 2. Remove Unkeyed Power Fuse from fuse holder. 3. Check voltage between the power side of the fuse and ground.

Is there voltage?

Check the Unkeyed Power Fuse. Is it blown?

Troubleshooting Procedure P0603 Keep-Alive Memory Error


P1105 Manifold Absolute Air Pressure (MAP) Sensor Signal – No Change Detected

This code is set if the MAP Sensor signal does not change for a calibrated amount of time. A disconnected, plugged or kinked MAP Sensor hose usually sets this code. Also ensure that the hose is routed so that any moisture in the hose will drain towards the engine, not the ECM.

P1106 Manifold Absolute Air Pressure (MAP) Slow Change After Crank

This code will set if the rate of MAP change is slower than the minimum calibrated value for post crank MAP change.

A restricted, plugged or kinked MAP Sensor hose usually sets this code. Also ensure that the hose is routed so that any moisture in the hose will drain towards the engine, not the ECM.

P1107 No Manifold Absolute Air Pressure (MAP) Change with Engine Stall

This code will set if the MAP measurement is the same during engine operation as it is after the engine is shut-off.

A disconnected, plugged or kinked MAP Sensor hose usually sets this code. Also ensure that the hose is routed so that any moisture in the hose will drain towards the engine, not the ECM.

P1133 UEGO Sensor Circuit Slow Response (Bank 1, Sensor 1)

This code indicates the Universal Exhaust Gas Oxygen Sensor (UEGO) does not respond quickly enough to what is expected. This will be indicated by an oscillating short term fuel trim value. This requires replacement of the UEGO Sensor.

P1134 UEGO Sensor Circuit No Activity Detected (Bank 1, Sensor 1)

Conditions to set Code:

This code will set if the Universal Exhaust Gas Oxygen Sensor (UEGO) heater does not heat the sensor enough.

No Yes

Fault: • Disconnected sensor. Fix: • Reconnect and confirm proper operation.

Check for a short between pin 3 and pin 4 on the UEGO Sensor wires

Is there a short?

No Yes

Fault: • UEGO Sensor is damaged internally. Fix: • Replace and confirm proper operation.

Fault: • UEGO heater is shorting out. Fix: • Repair and confirm proper operation.

Check the sensor connection.

Is it properly connected?

Troubleshooting Procedure P1134 UEGO Sensor Circuit – No Activity Detected (Bank 1, Sensor 1)


P1135 UEGO Sensor Calibration Error (Bank 1, Sensor 1)


This code will set when the ECM detects the Universal Exhaust Gas Oxygen Sensor (UEGO) pattern does not match the calibration.

No Yes


No Yes

Fault: • UEGO Sensor may be contaminated. Fix: • Replace the UEGO Sensor and confirm proper operation.

Fault: • There may be a fuel delivery problem. Fix: • See troubleshooting procedure P0171 & P0172.

Do the Following:

The vehicle should be stabilized at or around room temperature (approx. 70°F). 1. Turn ignition key off. 2. Connect a PC to a Datalink and the engine. 3. Start OmniWatch. 4. Start the engine. 5. Check the fuel trim values.

Is the fuel trim value changing fuel by more than 20%?



Troubleshooting Procedure P1135 UEGO Sensor Calibration Error (Bank 1, Sensor 1)


P1136 UEGO Sensor Pump Circuit Fault (Bank 1, Sensor 1)


The ECM has a diagnostic monitor on the TAN/YEL and TAN/ORG lines. A change in the pins will be considered a fault.

Troubleshooting Procedure P1136 UEGO Sensor Pump Circuit Fault (Bank 1, Sensor 1)



Yes No

The ECM has detected a fault in the TAN/YEL or TAN/ORG wires. Check for an open short in the wires and connection to the UEGO Sensor.

Did you find any problem?


Yes No

Fault: • Wiring or connector problem. Fix:

Check sensor resistance as per trouble code P1139.

Did this fix the problem? • Repair as required.

Yes No

Confirm there are no other trouble codes, and then confirm proper UEGO operation.

Replace the UEGO.

Did this fix the problem?

Yes No

Fault: • ECM UEGO Sensor circuit problem. Fix: • Replace the ECM.

Confirm there are no other trouble codes, and then confirm proper UEGO operation.


P1137 UEGO Sensor Reference Fault (Bank 1, Sensor 1)


The following code will be set when the Universal Exhaust Gas Oxygen Sensor (UEGO) reference voltage is shorted to ground. This fault may also be caused by electrical noise.

Troubleshooting Procedure P1137 UEGO Sensor Reference Fault (Bank 1, Sensor 1)



Yes No


No Yes

Fault: • Wiring or connector problem. Fix: • Repair as required.

Disconnect the UEGO Sensor and measure the voltage across the TAN/WHT and engine ground.

Does the voltage read 2.5v?

No Yes

Check engine block grounds and ignition coil wires.

Did you find a problem?

Clear the code and check if the DTC reappears.

Does the code reappear?

Fault: • ECM UEGO Sensor circuit problem. Fix: • Replace the ECM.

No Yes

Fix the problem and confirm proper operation.

No

Yes

The ECM has detected a fault in the TAN/YEL or TAN/ORG wires. Check for an open short in the wires and connection to the UEGO Sensor.

Did you find any problem?

Replace UEGO and confirm proper operation.


P1138 UEGO Sensor Heater Overheat (Bank 1, Sensor 1)


This code will set if an overheat condition on the heater is detected.

Troubleshooting Procedure P1138 UEGO Sensor Overheat (Bank 1, Sensor 1)

Yes No

Fault: With the key OFF disconnect the UEGO Sensor and use a test lamp between the RED/BLK and BLK/BLU wires.

• Short on heater wire. Fix: • Repair wire and replace UEGO Sensor. Does the lamp turn on?

No

Fix:

• Replace the UGEO Sensor.


P1139 UEGO Sensor Temperature Sense Cycle Fault (Bank 1, Sensor 1)


This code will set if the Universal Exhaust Gas Oxygen Sensor’s (UEGO) desired temperature does not equal that which it should be under the current engine operating condition.

Troubleshooting Procedure P1139 UEGO Sensor Temperature Sense Cycle Fault (Bank 1, Sensor 1)

Do the Following:

The vehicle should be stabilized at or around room temperature (approx. 70°F). 1. Turn ignition key off. 2. Connect a PC to a Datalink and the engine. 3. Start OmniWatch. 4. Start the engine. 5. Check the UEGO Sensor resistance.

Is the value between 80Ω and 150Ω?

Yes No

Fault:

P1231 CNG Leak Detected

This code is only used with systems that use the Falcon Pressure Regulator.

This code will set if PCNG drops more than the maximum pressure drop over the pressure drop test time. This test is performed only after the ignition is shut off and if the cylinder pressure is above 1015psi. These nominal settings are preset in the calibration file.

This test will only detect a leak downstream of the Regulator. Check all hoses and fittings for leaks and repair as needed.

Check the heater duty-cycle. • UEGO Sensor heater has failed.

Is the value below .8? Fix: • Replace UEGO Sensor and confirm proper operation.

Yes No

Fault: Fault: • Intermittent problem. • UEGO Sensor is faulty.

Fix:Fix: • Replace UEGO Sensor and confirm proper operation.

• See Troubleshooting Intermittent DTCs.


P1222 Throttle Position Sensor (TPS) Circuit Low Voltage


This code is triggered if the TPS Sensor voltage drops below its calibrated minimum value of approximately .2v for 1 second.

Troubleshooting Procedure P1222 Throttle Position Sensor Circuit Low Voltage

Do the Following:


Does TPS Raw read < .05v?

Yes No

Fault:Disconnect the sensor. • Fault is intermittent. Does TPS Raw read < .05v? Fix: • See intermittent TPS code P1224.

No Yes

Fault: Fault: • Sensor, connection at sensor, or signal wire in harness is shorted to ground or signal ground.

• Signal wire is shorted to power in the harness. Fix: • Check and repair as necessary. Fix:

• Repair or replace and confirm operation.


P1223 Throttle Position Sensor (TPS) Circuit High Voltage


This code is triggered if the TPS voltage goes above its calibrated minimum value of approximately 4.8v for 1 second.

Troubleshooting Procedure P1223 Throttle Position Sensor Circuit High Voltage

Do the Following:


Does TPS Raw read > 4.95v?

Yes No

Fault:Disconnect the sensor. • Fault is intermittent. Does TPS Raw read < .05v? Fix: • See intermittent TPS code P1224.

No Yes

Fault: Fault: • Sensor or connection at sensor. • Signal wire is shorted to power in the

harness. Fix: • Repair or replace and confirm operation. Fix:

• Check and repair as necessary.


P1224 Throttle Position Sensor (TPS) Circuit Intermittent


This code will set if the change in the TPS reading is higher than expected. E.g. if the throttle is not commanded to move and the TPS reading changes more than 1v within 1/128 second the code will set.

Troubleshooting Procedure P1224 Throttle Position Sensor Circuit Intermittent

Do the Following:


Does TPS Raw value jump when the harness is wiggled?

Yes No

Check: Move the throttle manually and watch the TPS Raw value. • Wiring between the ECM and the Sensor.

• Terminals at the ECM. • Terminals at the Sensor.

Does the TPS Raw reading change smoothly?

No Yes

Fault: Fault: • Fault is intermittent. • Motor or gears on the throttle body are

worn-out or damaged. Fix: • See Troubleshooting Intermittent DTCs. Fix:



P1244 Wastegate Over-boost


This code is set if the detected boost is higher than the calibrated amount for around 1 second.


The resistance of the wastegate solenoid.

The electrical connections.

Plumbing of boost, solenoid and wastegate connections.

Linkage of the wastegate.

Leaking wastegate diaphragm.

P1245 Wastegate Performance


This code will set if the desired boost does not equal the actual boost measured by either a Boost Sensor or MAP Sensor for a calibrated amount of time.


The resistance of the wastegate solenoid.

The electrical connections.

Plumbing of boost, solenoid and wastegate connections.

Linkage of the wastegate.

Leaking wastegate diaphragm.

Check for engine misfire by referring to the Engine Roughness Parameter in OmniWatch, it should be below .1.

A clogged air filter.

A plugged exhaust system.

P1246 Wastegate Oscillating


This code will set if the boost is centered at the desired boost but is not stable and oscillates by more than 1 or 2psi. The typical test length for this code is 5-20 seconds and depends on the particular application.


A sticking solenoid.

A sticking wastegate.

Restricted wastegate control piping.

Check for engine misfire by referring to the Engine Roughness Parameter in OmniWatch, it should be below .1.


P1272 Accelerator 1 Pedal Position (APP1) Circuit Low Voltage


This code is triggered if the APP1 Sensor voltage drops below its calibrated minimum value of approximately .2v for 1 second.

Do the Following:


Does APP1 Raw read < .05v?

No Yes

Fault: • Fault is intermittent. Fix: • See intermittent APP1 code P1274.



No Yes

Troubleshooting Procedure P1272 Accelerator 1 Pedal Position Circuit Low Voltage





P1273 Accelerator 1 Pedal Position (APP1) Circuit High Voltage


This code is triggered if the APP1 Sensor voltage goes above its calibrated minimum value of approximately 4.8v for 1 second.

Troubleshooting Procedure P1273 Accelerator 1 Pedal Position Circuit High Voltage

Do the Following:


Does APP1 Raw read > 4.95v?

Yes No

Fault:Disconnect the sensor. • Fault is intermittent. Does APP1 Raw read < .05v? Fix: • See intermittent APP1 code P1274.

No Yes





P1274 Accelerator 1 Pedal Position (APP1) Intermittent


This code will set if the change in the APP1 Sensor reading is higher than expected. E.g. if the throttle is not commanded to move but the APP1 Sensor reading changes more than 1v within 1/128 second the code will set.

Troubleshooting Procedure P1274 Accelerator 1 Pedal Position Intermittent

Do the Following:


Does the APP1 Raw value jump when the harness is wiggled?

Yes No

No Yes

Check:

Fault: • Sensor is worn. Fix: • Check and repair as necessary.


Move the throttle manually and watch the APP1 Raw value. • Wiring between the ECM and the Sensor.

• Terminals at the ECM. Does the APP1 Raw reading change smoothly? • Terminals at the Sensor.


P1276 Accelerator 2 Pedal Position (APP2) Circuit Low Voltage


This code is triggered if the APP2 Sensor voltage drops below its calibrated minimum value of approximately .2v for 1 second.

Troubleshooting Procedure P1276 Accelerator 2 Pedal Position Circuit Low Voltage

Do the Following:



Yes No


No Yes





P1277 Accelerator 2 Pedal Position (APP2) Circuit High Voltage


This code is triggered if the APP2 Sensor voltage goes above its calibrated minimum value of approximately 4.8v for 1 second.

Troubleshooting Procedure P1277 Accelerator 2 Pedal Position Circuit High Voltage

Do the Following:


Does APP2 Raw read > 4.95v?

Yes No


No Yes





P1278 Accelerator 2 Pedal Position (APP2) Intermittent


This code will set if the change in the APP2 Sensor reading is higher than expected. E.g. if the throttle is not commanded to move but the APP2 Sensor reading changes more than 1v within 1/128 second the code will set.

Troubleshooting Procedure P1278 Accelerator 2 Pedal Position Intermittent

Do the Following:


Does the APP2 Raw value jump when the harness is wiggled?

Yes No

No Yes

Check:

Fault: • Sensor is worn. Fix: • Check and repair as necessary.


Move the throttle manually and watch the APP2 Raw value. • Wiring between the ECM and the Sensor.

• Terminals at the ECM. Does the APP2 Raw reading change smoothly? • Terminals at the Sensor.


P1335 Crankshaft or Camshaft Position Sensor Circuit Malfunction


This code will set if for several seconds the signal from the Camshaft Position Sensor or Crankshaft Position Sensor does not match the signal which the ignition controller expects to see.

The design of the mask and signal appearance depends on the engine application.

Actions Taken By ECM:

This code is only active when the ECM system is used in conjunction with the AFS Distributor-less Ignition System.

Rotation

This falling edge should occur at 10ºBTDC on the compression stroke of cylinder no.1.

5V

0V

1 complete engine cycle(2 engine revolutions)


P1350 Ignition Coil Primary/Secondary Circuit Malfunction

This code will trigger if the Ignition Module detects that less than 80% of the peak expected Ignition Coil current is being used for a minimum of 30 engine cycles.


P1351 Ignition Coil Secondary Circuit Malfunction

This code will set if the energy from the Ignition Coil is fed back into the Ignition Controller as the module attempts to fire the spark plug. The Ignition Module will also shut off the malfunctioning Ignition Coil for several engine revolutions then it will re-try. The Malfunction Indicator Lamp will be illuminated but will turn off if the malfunction is corrected. The code will remain in history.


P1352 Ignition Timing Circuit Malfunction

This code will be triggered if the Ignition Controller does not receive a signal on the Spark Angle Word (SAW) line.


P1501 No Vehicle Acceleration with High Throttle


This code will set if TPS is > 50%, MAP is > 10psi, and VSS is < 75mph for 64 seconds.

P1502 High RPM at Very Light Load


This code will set if RPM is > 4800 and MAP is < 8psi for 64 seconds.

P1506 Idle Air Controller (IAC) Low Airflow


This code will set if the IAC has opened all the way and the engine idle speed is too low.

P1507 Idle Air Controller (IAC) High Airflow


This code will set if the IAC has closed all the way but the engine idle speed is too high.


P1514 Throttle Flow Error


This code is set if the MAP and throttle position do not correlate with each other correctly. The tolerances are calibrated to the engine and throttle body.

Troubleshooting Procedure P1514 Throttle Flow Error

P1515 Throttle Flow Error at Idle


This code is set if the MAP and throttle position do not correlate with each other correctly. The tolerances are calibrated to the engine and throttle body.

No Yes


Check the following: Check and troubleshoot other codes first. • Disconnected MAP Sensor or MAP hose.

• Intake leaks. • Collapsed air inlet piping. • Clogged air filter. • Plugged exhaust system.

Troubleshooting Procedure P1515 Throttle Flow Error at Idle

No Yes


Check the following: Check and troubleshoot other codes first. • Disconnected MAP Sensor or MAP hose.

• Intake leaks. • Collapsed air inlet piping. • Clogged air filter. • Plugged exhaust system. • Incorrect throttle span.


P1560 Injector Power Relay Stuck Shorted


This code will set if the Regulator power is at battery volts when commanded off.

Troubleshooting Procedure P1560 Injector Power Relay Stuck Shorted

No Yes


Check for a short between the RED/BLK to battery power. Check and troubleshoot other codes first.

Is there a short?

Yes No

Turn off the key for 1 minute and check for voltage at the Injector connector. Fix the wiring and clear the DTC.

Does it equal battery voltage?

Yes No

Fault: Fault: • ECM is damaged. • Fault is intermittent. Fix: Fix: • Replace ECM. • See Troubleshooting Intermittent DTCs.


P1561 Injector Power Relay Stuck Open


This code will set if there is a short to ground or there is an overheated ECM and will likely result in a no start condition.

Troubleshooting Procedure P1561 Injector Power Relay Stuck Open

No Yes


Check for a short between the RED/BLK to ground or BLK wires on the Injector to the Injector body.

Check and troubleshoot other codes first.

Is there a short?

Yes No

Fault: Fix the wiring and clear the DTC. • ECM is damaged.

Fix: • Replace ECM.



P1606 Incompatible Calibration File

This code will be set if the calibration file is not compatible with the firmware file.

If this code is set, check both the firmware and calibration files and replace the incompatible file with the correct file. Check your application guide for the correct firmware and calibration files for your application.

P1609 Programmed Feature Not Compatible with Hardware

This code will be set if there is a feature selected in the calibration file which is not compatible with the hardware installed with the system.

If this code is set, check the calibration file against the application, if the installed calibration file is the correct file for the application, contact Omnitek Engineering for assistance. If the file does not match the application, send the correct calibration file. Clear the codes and confirm proper operation.

diesel-to-natural gas (dng) conversion manual … dng conversion packet.pdfconversion requires...

Documents