TB 107: Installation of Ford 6.0L Powerstroke Injectors

GB Technical Bulletin #107

Note: This TB is included in the box with GB part numbers 722-506 and 722-507 remanufactured fuel injectors. It is being provided on-line for the benefit of our customers.

Fuel Injector Replacement Tips

Proper installation of the Ford 6.0L Powerstroke injector is critical for proper engine operation. Improper installation can result in severe engine damage and unecessary warranty claims. GB has determined, based on the analysis of injectors returned as warranty defects, that many injector failures are the result of improper installation procedures or defects in the engine’s fuel delivery system. These types of injector failure are NOT covered under GB’s limited warranty.

Missing Copper Washer or Improperly Torqued Injectors (Figure 1)

A missing copper washer or improperly torqued injector can allow hot combustion gases into the injector cavity. This will result in failure of the lower fuel o-ring on the injector causing fuel leakage into the combustion chamber when the engine is turned off and hot combustion gases into the fuel system when the engine is running.

Fuel leakage into the combustion chamber can result in hydro-static engine lock-up and engine failure. This will occur when the engine is shut off and the fuel drains past the injectors tip into the combustion chamber.

Combustion gases leaked into the fuel system will result in siezure of the fuel injector’s internal components and multiple injector failure. Since all of the injectors share a common fuel rail within the cylinder head a combustion leak into the fuel system will contaminate all of the injectors.

Black soot on the bottom of the injector is a clear indicator that the injector was improperly torqued or the copper washer was missing.

Fig 1: Missing Copper Washer or Improper Injector Torque

 

High Pressure O-Ring Failure (Figure 2 & 3)

Improper alignment of the oil rail ball tubes during installation can result in damage to the high pressure o-ring resulting in oil leakage. Often this occurs after installation and an extended period of operation, rather than immediately after installation. Ensure ball tubes are free from damage or “grooving” on the ball valve stem. If grooving or other damage is present the oil rail should be replaced.

Fig 2: High Pressure O-Ring Failure from Ball Tube Mis-Alignment

Fig 3: Ensure Ball Tubes are Damage Free

 

Fuel Contamination – Split Injector Tip (Figure 4)

Fuel contaminated with water, air or debris can cause injector tip failure resulting in sever engine damage. Fuel is used to cushion the needle in the nozzle. The lack of fuel at the nozzle, caused by air in the system, low fuel pressure or no fuel pressure can result in this type of failure. Water lacks the characteristics of diesel fuel for lubricity, viscosity and specific gravity. Water present in the fuel can result in fracturing of the nozzle tip.

Fig 4: Split Injector Tip

Installation Tips – Be Sure:

  • Copper washer is present on injector being REPLACED.
  • Copper washer is present on REPLACEMENT injector.
  • Ensure ball tubes are free from grooving, nicks, burrs or other damage.
  • Oil rail ball tubes are centered and properly aligned.
  • Injector is properly torqued – see service manual.
  • Engine oil is clean and at the proper level.
  • Fuel supply is free from water, air and contamination.
  • Fuel pressure is at the manufacturers recommendation.
  • Injector sleeve is clean and damage-free.
  • Engine coolant shows no sign of engine oil (sleeve failure).

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TB 106: Installation of Ford 7.3L Powerstroke Injectors

GB Technical Bulletin #106

Note: This TB is included in the box with GB part numbers 722-501, 722-502, 722-503, 722-504 and 722-505 remanufactured fuel injectors. It is being provided on-line for the benefit of our customers.

Fuel Injector Replacement Tips

Proper installation of the Ford 7.3L Powerstroke injector is critical for proper engine operation. Improper installation can result in severe engine damage and unecessary warranty claims. GB has determined, based on the analysis of injectors returned as warranty defects, that many injector failures are the result of improper installation procedures or defects in the engine’s fuel delivery system. These types of injector failure are NOT covered under GB’s limited warranty.

Missing Copper Washer or Improperly Torqued Injectors (see figure 1)

A missing copper washer or improperly torqued injector can allow hot combustion gases into the injector cavity. This will result in failure of the lower fuel o-ring on the injector causing fuel leakage into the combustion chamber when the engine is turned off and hot combustion gases into the fuel system when the engine is running.

Fuel leakage into the combustion chamber can result in hydro-static engine lock-up and engine failure. This will occur when the engine is shut off and the fuel drains past the injectors tip into the combustion chamber.

Combustion gases leaked into the fuel system will result in siezure of the fuel injector’s internal components and multiple injector failure. Since all of the injectors share a common fuel rail within the cylinder head a combustion leak into the fuel system will contaminate all of the injectors.

Black soot on the bottom of the injector is a clear indicator that the injector was improperly torqued or the copper washer was missing.

Fuel Contamination – Split Injector Tip (see figure 2)

Fuel contaminated with water, air or debris can cause injector tip failure resulting in sever engine damage. Fuel is used to cushion the needle in the nozzle. The lack of fuel at the nozzle, caused by air in the system, low fuel pressure or no fuel pressure can result in this type of failure. Water lacks the characteristics of diesel fuel for lubricity, viscosity and specific gravity. Water present in the fuel can result in fracturing of the nozzle tip.

Installation Tips – Be Sure:

  • Copper washer is present on injector being REPLACED.
  • Copper washer is present on REPLACEMENT injector.
  • Injector is properly torqued – see service manual.
  • Engine oil is clean and at the proper level.
  • Fuel supply is free from water, air and contamination.
  • Fuel pressure is at the manufacturers recommendation.
  • Injector sleeve is clean and damage-free.
  • Engine coolant shows no sign of engine oil (sleeve failure).

Figure 1 - Missing Copper Washer

Figure 2 - Split Injector Tip

 

[1173]

Categories: Ford 7.3L Power Stroke Tags:

Ford 7.3L Powerstroke Special Code Clearing Procedure For Injector Driver Module (IDM) Codes

After extensive testing GB has determine a condition that exists with the Ford IDS software and other scan tools that can result in replacement non-defective components or unnecessary diagnostic time. In some cases the Ford IDS software will report Diagnostic Trouble Codes (DTCs) that may not be present.

Ford IDS Software

When IDM codes are present and codes are erased using the FORD IDS software or other scan tools a RETEST is necessary to determine if codes are persistent and faults are present. The ERASE codes function in the Ford IDS software will mis-report that codes are still present after the erase procedure is completed. This gives the appearance that the IDM may be defective and that the codes cannot be erased, or there are hard faults present when in fact the faults could have been corrected by the replacement of the IDM or other components. This is especially true when there are no driveability concerns and diagnostic pin-point test have not detected an issue.

During the erase codes process the Ford IDS software appears to recheck for codes after the erase procedure. If Injector Driver Module Codes (IDM) or Injector Circuit Codes were present, the same codes are displayed even after the erase procedure. In some cases the IDS software will provide the a warning screen indicating “Some modules may display CMDTCs after they have been erased. If CMDTCs remain, press RETEST” to indicate this issue, however this is not always the case as verified during vehicle testing.

Corrective Action

After errasing codes always press the RETEST button on the Ford IDS software to retrieve active diagnostic trouble codes. The retest button is NOT clearly labeled but located on the bottom of the Ford IDS software beneath the erase codes button (see image below).

Aftermarket Scan Tools

Aftermarket scan tools may exhibit the same issue as the Ford IDS software described above. In this case it is recommended to Clear DTCs then re-run the self test to determine if DTCs are present. If DTCs appear to be persistent it may be necessary to remove the scan tool, reinstall and recheck for DTCs by re-running the self-test.

Categories: Ford 7.3L Power Stroke Tags:

Ford 7.3L Cylinder Contribution or Misfire Fault – DTC Diagnostics

This article applies to Diagnostic Trouble Codes (DTC): P0263, P0266, P0269, P0272, P0275, P0278, P0281, P0284 and P0301, P0302, P0303, P0304, P0305, Po306, P0307, P0308 for the Ford 7.3L Powerstroke.

These diagnostic codes indicate that the Powertrain Control Module (PCM) has detected that one or more cylinders are misfiring and non-contributing. The PCM continually monitors all cylinders for proper operation. If it detects a cylinder is misfiring or not contributing it will store a Diagnostic Trouble Code (DTC) to indicate the misfire and identify the cylinder in question. See the Ford 7.3L Diagnostic Trouble Code (DTC) Index to identify the specific cylinder. It is possible that these DTCs are cause by an engine mechanical problem.

Possible causes for any of these codes include:

Low cylinder compression

Low compression in one or more cylinders can result in cylinder contribution or misfire Diagnostic Trouble Codes. A compression test should be performed to determine if this is the cause of the DTC. Possible causes for low compression include:

  • Broken compression rings.
  • Leaking or bent intake or exhaust valves.
  • Bent push rod(s).
  • Broken rocker arms or retaining bolts.
  • Bent connecting rod.
  • Cylinder head gasket failure.

Low Fuel Pressure or Poor Fuel Quality

Low fuel pressure or poor fuel quality can result in cylinder misfire. You should suspect this if you have received multiple cylinder misfire codes. A fuel pressure test should be performed to determine if the fuel pressure is adequate (40-80 psi). A fuel sample should be obtained and checked for contamination and or water. Possible causes of low fuel pressure include:

  • Restricted fuel filter.
  • Defective fuel pump.
  • Defective fuel pressure regulator.
  • Fuel contamination (water, dirt)

Improper Injection Control Pressure (ICP) / Oil Aeration

Proper Injection Control Pressure is critical for the proper operation of the 7.3L Powerstroke injection system. Poor oil quality or oil aeration can result in an engine misfire because the injectors are hydraulically controlled. Causes of oil aeration include:

  • Extended oil change intervals resulting in depletion of anti-foaming additives in oil.
  • Air present in hydraulic system as a result of recent engine or high pressure oil system repair.
  • Wrong type or grade of engine oil.
  • Oil contaminated with fuel or oil.

Faulty Fuel Injector

A faulty fuel injector can result in a cylinder misfire. If other diagnostic codes are present that indicate an injector circuit fault those diagnostic codes should be diagnosed first. If engine mechanical problems and injector electrical circuit problems have been ruled out Ford recommends the replacement of the fuel injector in the affected cylinder. It is important to inspect the injector sleeve inside the cylinder head prior to installing a new injector.

 

 

Categories: Ford 7.3L Power Stroke Tags:

Ford 7.3L Diagnostic Trouble Code (DTC) Index

The following Diagnostic Trouble Code (DTC) index is provided for your conveniece. These codes are specific to the Ford 7.3L Powerstroke. Codes listed in blue will link to helpful diagnostic tips and test procedures. Always consult factory service manuals and vehicle specific diagnostic procedures.

P1111 System Pass (No DTCs Available)

P0107 BARO Circuit Low Input

P0108 BARO Circuit High Input

P0112 IAT Sensor Circuit Low Input

P0113 IAT Sensor Circuit High Input

P0122 Accelerator Pedal Sensor Circuit Low Input

P0123 Accelerator Pedal Sensor Circuit High Input

P0197 EOT Sensor Circuit Low Input

P0198 EOT Sensor Circuit High Input

P0220 Throttle Switch B Circuit Malfunction

P0221 Throttle Switch B Circuit Performance

P0230 Fuel Pump Relay Driver Fail

P0231 Fuel Pump Relay Driver Circuit Failure

P0232 Fuel Pump Relay Driver Failed Off

P0236 Turbo Boost Sensor A Circuit Performance

P0237 Turbo Boost Sensor A Circuit Low Input

P0238 Turbo Boost Sensor A Circuit High Input

P0261 Injector Circuit Low – Cylinder 1

P0262 Injector Circuit High – Cylinder 1

P0263 Cylinder 1 Contribution/Balance Fault

P0264 Injector Circuit Low – Cylinder 2

P0265 Injector Circuit High – Cylinder 2

P0266 Cylinder 2 Contribution/Balance Fault

P0267 Injector Circuit Low – Cylinder 3

P0268 Injector Circuit High – Cylinder 3

P0269 Cylinder 3 Contribution/Balance Fault

P0270 Injector Circuit Low – Cylinder 4

P0271 Injector Circuit High – Cylinder 4

P0272 Cylinder 4 Contribution/Balance Fault

P0273 Injector Circuit Low – Cylinder 5

P0274 Injector Circuit High – Cylinder 5

P0275 Cylinder 5 Contribution/Balance Fault

P0276 Injector Circuit Low – Cylinder 6

P0277 Injector Circuit High – Cylinder 6

P0278 Cylinder 6 Contribution/Balance Fault

P0279 Injector Circuit Low – Cylinder 7

P0280 Injector Circuit High – Cylinder 7

P0281 Cylinder 7 Contribution/Balance Fault

P0282 Injector Circuit Low – Cylinder 8

P0283 Injector Circuit High – Cylinder 8

P0284 Cylinder 8 Contribution/Balance Fault

P0301 Cylinder 1 Misfire Detected

P0302 Cylinder 2 Misfire Detected

P0303 Cylinder 3 Misfire Detected

P0304 Cylinder 4 Misfire Detected

P0305 Cylinder 5 Misfire Detected

P0306 Cylinder 6 Misfire Detected

P0307 Cylinder 7 Misfire Detected

P0308 Cylinder 8 Misfire Detected

P0340 CMP Sensor Circuit Malfunction

P0341 CMP Sensor Circuit Performance

P0344 CMP Sensor Circuit Intermittent

P0360 Glow Plug Circuit Malfunction

P0381 Glow Plug Indicator Circuit Malfunction

P0460 Fuel Tank Level Indicator Circuit Malfunction

P0470 Exhaust Back Pressure Sensor Circuit Malfunction

P0471 Exhaust Back Pressure Sensor Circuit Performance

P0472 Exhaust Back Pressure Sensor Circuit Low Input

P0473 Exhaust Back Pressure Sensor Circuit High Input

P0476 Exhaust Pressure Control Valve Malfunction

P0476 Exhaust Pressure Control Valve Performance

P0478 Exhaust Pressure Control Valve High Input

P0500 Vehicle Speed Sensor (VSS) Malfunction

P0503 Vehicle Speed Sensor Noisy

PO541 Manifold Intake Air Heater

P0542 Manifold Intake Air Heater

P0560 System Voltage Malfunction

P0662 System Voltage Low

P0563 System Voltage High

P0666 Cruise ‘On” Signal Malfunction

P0566 Cruise “Off’ Signal Malfunction

P0667 Cruise ‘Resume’ Signal Malfunction

P0668 Cruise “Set’ Signal Malfunction

P0669 Cruise “Coast’ Signal Malfunction

P0571 Brake Svdtch A Circuit Malfunction

P0603 Internal Control Module KAM Error

P0605 Internal Control Module ROM Error

PO606 PCM Processor Fault

P0640 Manifold Intake Air Heater

P0670 Glow plug control circuit malfunction

P0671 Glow plug #1 circuit failure

P0672 Glow plug #2 circuit failure

P0673 Glow plug #3 circuit failure

P0674 Glow plug #4 circuit failure

P0675 Glow plug #5 circuit failure

P0676 Glow plug #6 circuit failure

P0677 Glow plug #7 circuit failure

P0678 Glow plug #8 circuit failure

P0683 Glow plug diagnostic signal communication fault

P0703 Brake Switch B Circuit Malfunction

P0704 Clutch Pedal Position Switch Input Circuit Malfunction

P0705 TR Sensor Circuit Malfunction

P0707 TR Sensor Circuit Low Input

P0708 TR Sensor Circuit High Input

P0712 Transmission Fluid Temp. Sensor CKT Low Input

P0713 Transmission Fluid Temp. Sensor CKT High Input

P0715 TSS Sensor Circuit Malfunction Fault

P0717 TSS Intermittent Failure

P0718 Noisy TSS

P0720 OSS Sensor Circuit Malfunction

P0721 Noisy OSS

P0722 OSS Intermittent Failure

P0732 Gear Two Ratio Error

P0733 Gear Three Ratio Error

P0741 TCC Circuit Performance

P0743 Torque Converter Clutch System Electrical Failure

P0750 Shift Solenoid 1 Malfunction

P0755 Shift Solenoid B Malfunction

P0781 1-2 Shift Malfunction

P0782 2-3 Shift Malfunction

P0783 3-4 Shift Malfunction

P1000 OBD 11 Monitor Checks Not Complete. More Driving Required

P1105 Dual Alternator Upper Fault (Monitor)

P1106 Dual Afternator Lower Fault (Control)

P1107 Dual Alternator Lower Circuit Malfunction (Control)

P1108 Dual Alternator BATT Lamp Circuit Malfunction

P1118 Manifold Air Temperature Sensor Low Input

P1119 Manifold Air Temperature Sensor High Input

P1139 Water in Fuel Indicator Circuit Malfunction

P1140 Water in Fuel Condition

P1184 Engine Oil Tamp Sensor Circuit Performance

P1209 Injection Control System Pressure Peak Fault

P1210 Injection Control Pressure Above Expected Level

P1211 ICP Not Controllable – Pressure Abow/Below Desired

P1212 ICP Voltage Not at Expected Level

P1218 CID Stuck High

P1219 CID Stuck Low

P1247 Turbo Boost Pressure Low

P1248 Turbo Boost Pressure Not Detected

P1249 Wastagate Fail Steady State Test

P1250 Electronic Passive Anti-Theft? System

P1261 High to Low Side Short – Cylinder 1

P1262 High to Low Side Short – Cylinder 2

P1263 High to Low Side Short – Cylinder 3

P1264 High to Low Side Short – Cylinder 4

P1265 High to Low Side Short – Cylinder 5

P1266 High to Low Side Short – Cylinder 6

P1267 High to Low Side Short – Cylinder 7

P1268 High to Low Side Short – Cylinder 8

P1271 High to Low Side Open – Cylinder 1

P1272 High to Low Side Open – Cylinder 2

P1273 High to Low Side Open – Cylinder 3

P1274 High to Low Side Open – Cylinder 4

P1275 High to Low Side Open – Cylinder 5

P1276 High to Low Side Open – Cylinder 6

P1277 High to Low Side Open – Cylinder 7

P1278 High to Low Side Open – Cylinder 8

P1280 ICP Circuit Out of Range Low

P1281 ICP Circuit Out of Range High

P1282 Excessive ICP

P1263 IPR Circuit Failure

P1284 ICP Failure – Aborts KOER or CCT Test

P1291 High Side No. 1 (Right) Short to GND or B+

P1292 High Side No. 2 (Left) Short to GND or B+

P1293 High Side Open Bank No. 1 (Right)

P1294 High Side Open Bank No. 2 (Left)

P1295 Multiple Faults on Bank No. 1 (Right)

P1296 Multiple Faults on Bank No. 2 (Left)

P1297 High Sides Shorted Together

P1298 IDM Failure

P1316 Injector Circuit/IDM Codes Detected

P1391 Glow Plug Circuit Low Input Bank No. 1(Right)

P1393 Glow Plug Circuit Low Input Bank No. 2 (Left)

P1395 Glow Plug Monitor Fault Bank No. 1

P1396 Glow Plug Monitor Fault Bank No. 2

P1397 System Voltage Out of Self Test Range

P1464 A/C On During KOER or CCT Test

P1501 VSS Out Of Self Test Range

P1502 Invalid Self Test – APCM Functioning

P1531 Invalid Test -Accelerator Pedal Movement

P1536 Parking Brake Applied Failure

P1662 IDM EN Circuit Failure

P1663 FDCS Circuit Failure

P1667 CID Circuit Failure

P1668 PCM -IDM Diagnostic Communication Error

P1670 EF Feedback Signal Not Detected

P1690 Wastegate Control Valve Malfunction

P1702 TRS Sensor Intermittent Circuit Malfunction

P1704 Digital TRS Failed to Transition State

P1705 TR Sensor out of Self Test Range

P1711 TFT Sensor Out of Self Test Range

P1713 TFT Stuck in Range Low: Below 50 Deg F

P1714 Shilt Solenoid A Inductive Signature Malfunction

P1715 Shift Solenoid B Inductive Signature Malfunction

P1718 TFT Stuck in Range High: Above 25O Deg F

P1728 Transmission Slip Error

P1729 4x4L Switch Error

P1744 Torque Converter Clutch System Performance

P1746 EPC Solenoid Open Circuit

P1747 EPC Solenoid Short Circuit

P1754 CCS (Solenoid) Circuit Malfunction

P1760 EPC Solenoid Short Intermittent

P1780 TCS Circuit Out of self Test Range

P1781 4x4L Circuit Out of Self Test Range

P1783 Transmission Overtemperature Condition

Categories: Ford 7.3L Power Stroke Tags:

Ford 7.3L Injector Circuit Fault – DTC Diagnostics

This article applies to Diagnostic Trouble Codes (DTC): P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0273, P0274, P0276, P0277, P0279, Po280, P0282, P0283 for the Ford 7.3L Powerstroke.

Note: If you have replaced an IDM and the engine is running smoothly and you are receiving any of these codes you should:

  • Clear the diagnostic trouble codes using a scan tool.
  • Remove the scan tool from the vehicle. If you are using Ford IDS software please see this article for special information regarding clearing codes.
  • Start and run the engine.
  • Reinstall scan tool and recheck for diagnostic trouble codes.

Some diagnostic codes may be a remnant of the prior IDM and these codes may be the result of a prior fault that may no longer be present. It is always advisable to clear codes and confirm a fault is present prior to performing lengthy diagnostic procedures.

These diagnostic codes indicates that the IDM has detected a fault in the injector control circuits. The IDM continually monitors the injector circuits for proper operation. If the IDM detects one of the ground control circuits is shorted to battery voltage or the injector supply voltage (115V DC), or the supply voltage is shorted to ground it will store an appropriate diagnostic code to help you diagnose the circuit. The Diagnostic Trouble Code (DTC) will identify the affected injector circuit and type of failure detected. See the Ford 7.3L Diagnostic Trouble Code index for identification of the specific cylinder/circuit.

DTCs P0262, P0265, P0268, P0271, P0274, P0277, P0280, P0283 indicate that the IDM has detected a low side (injector ground circuit) short to voltage.

DTCs P0261, P0264, P0267, P0270, P0273, P0276, P0279, P0282 indicate that the IDM has detected an injector circuit is shorted to ground.

GB has developed the following Technical Service Bulletin to help diagnose these Diagnostic Trouble Codes (DTCs).

To learn more about the operation of the IDM module you may refer to this article: Ford 7.3L Powerstroke IDM Operation.

Categories: Ford 7.3L Power Stroke Tags:

Clean Diesel

You’ve probably heard the term “Clean Diesel” used in the automotive industry recently. That’s because vehicle manufacturers, the petroleum industry and many trade organizations have invested heavily in developing and promoting this new technology. The goal is to clean up diesel emissions to meet new federal and European standards while at the same time exploiting diesel’s fuel economy advantage and improving the public perception of diesel. Clean diesel technology represents a significant achievement in meeting these goals. Let’s take a look at Clean Diesel: what it is, and what it is not.

The Technology

Clean Diesel is not one particular technology or component, it’s a system of multiple pieces working together to clean up diesel emissions. This includes combustion technology, exhaust after-treatment, fuel reformulation and advanced electronics. First, let’s look at the problem with diesels that Clean Diesel Technology is designed to address.

Diesels are the most efficient internal combustion engine available. However, two things have stood as obstacles to diesel; Particulate Emissions and Nitrogen Oxide Emissions, better known as NOx. Particulate emissions are characterized by that black sooty plume of smoke you see coming out of the exhaust. NOx emissions cause harmful ground-level ozone (smog) and acid rain.

A combined catalytic converter and Diesel Particulate Filter. Using a catalyst, Ultra Low Sulfur Diesel fuel and sophisticated injection can result in a 25%-50% reduction in NOx and a 90% reduction in particulate emissions. Image courtesy of the Diesel Technology Forum.

NOx Emissions

NOx emissions are created when fuels are burned at high temperatures. There are two primary methods to reduce NOx emissions.

The first method, which addresses the control of combustion temperatures, is the use of Exhaust Gas Recirculation (EGR). EGR reduces combustion temperatures by recirculating exhaust back into the intake system where it is drawn back into the combustion chamber. At first, it would seem this would increase combustion temperature because the temperature of the exhaust gas is much higher than the intake air charge. However, EGR works in another way. Exhaust gas has less oxygen content than air, which contains about 21% oxygen. Because of this, the exhaust gas is considered inert to the combustion process. When exhaust gas is added to the combustion chamber it consumes volume that would otherwise be occupied by oxygen rich air. By removing oxygen from the combustion chamber the temperature of the combustion process is reduced, thus reducing NOx emissions.The second method to reduce NOx is the use of exhaust after-treatment devices such as a catalytic converter. Prior to 2007 catalysts could not be used on diesels because of the high sulfur content in diesel fuel, which would quickly contaminate the catalytic converter. In 2007 the federal government mandated that diesel fuel be reformulated to contain less than 15 parts per million of sulfur content. Prior to this federal mandate, diesel contained up to 500 parts per million of sulfur. This new fuel is referred to as Ultra Low Sulfur Diesel fuel or ULSD.

Particulate Emissions

Diesel engines inject fuel directly into the combustion chamber.  The time that the fuel has to mix with the air is very short compared to gasoline engines, where the fuel is injected into the intake manifold. This can result in inconsistent air fuel mixtures within the combustion chamber resulting in incomplete combustion, which causes particulate emissions. In order to reduce particulate emissions, manufacturers utilize a Diesel Particulate Filter (DPF). The filter works by trapping the carbon particles present in the exhaust on a substrate within the filter. Over time, the substrate will build up with particulates and begin to restrict the exhaust gas flow, causing decreased engine performance. In order to prevent this, the DPF is regenerated on a periodic basis. This process heats the filter’s substrate to temperatures that allow the soot to be burned off. Regeneration is controlled by the vehicles Engine Control Unit (ECU) which monitors particulate build up using sophisticated software models and exhaust system pressure readings. Regeneration must be carried out approximately every 200 to 500 miles, but this varies significantly based on vehicle operating conditions. A typical regeneration cycle can last between 10-15 minutes. The regeneration process begins with the ECU retarding the fuel injection event while adding an injection event after the main injection pulse. This increases the exhaust gas temperature to the necessary levels for regeneration. The high exhaust temperature heats the filter substrate and the soot is burned off and turned to ash. The DPF stores the ash for the life of the vehicle.

Clean Diesel Technology results in a 25%-50% reduction in NOx emissions and a 90% reduction in particulate emissions, solid proof that diesels are cleaning up their act.

To learn more about Clean Diesel Technology visit www.gbreman.com or the Diesel Technology Forum at www.dieselforum.org.

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TB 105: Identification of GM Duramax Injectors

 GB Technical Bulletin #105
 
The injector for the GM Duramax from 2004 through the current model year look identical, with the exception of the keying inside the plastic connector.
GM Duramax Injector

 

The GB part number for each injector can be identified using the following guide:

732-501 – Duramax LLY 2004-05

-

732-503 - Duramax LBZ 2006-07

-
732-504 – Duramax LMM 2007.5-10

 

[1168]

Categories: Technical Bulletins Tags:

Aftermarket New Injectors – One Size Fits None

The economic down-turn has resulted in fierce competition from the original equipment manufacturers (OEM) for out of warranty maintenance and repair. National television and print ads reinforce the use of “genuine OEM replacement parts installed by your local dealer to ensure a quality repair.”

When the consumer is confronted with choosing an OEM part or aftermarket replacement part on an older vehicle they will usually choose the aftermarket part.  Typically, this choice is based solely on its price, assuming the quality of the parts are equal. However this is not always the case.

It is up to each aftermarket manufacturer to ensure their replacement parts meet or exceed OEM specifications. Most aftermarket manufacturers make an honest effort to ensure this is the case because technicians and repair facilities rely heavily on the aftermarket industry to provide high quality parts at a fraction of the cost of OEM parts. This cost advantage, in addition to great service, allows the independent repair facility to easily compete with their local dealerships.

One area of concern within the aftermarket is part consolidation. Many years ago the aftermarket was satisfied supplying a thermostat gasket with 10 different bolt-hole patterns. The technician or DIY’er just rotated it until two of the holes lined up with the holes in the housing. In most cases none of the holes aligned properly and you ended up having to punch new holes or cobble something together. Not good.

With engine management components and especially with fuel injectors, it is critical that the aftermarket replacement meet OEM specifications, all of the specifications, not just some.

With over 25 years of remanufacturing experience GB has a unique perspective on fuel injectors and we are starting to see some alarming trends in consolidated aftermarket new injectors.

Spray Pattern

Engine designers work closely with injector manufacturers to match the OEM injector to the engine. This includes ensuring the injector’s spray pattern is properly matched to intake runner design, cylinder head geometry and provides the necessary fuel atomization properties. The vehicle manufacturer then tunes the engine for all operating conditions via the software in the Powertrain Control Module (PCM) based on the injector’s characteristics, among other parameters.

The spray pattern shape and atomization properties are controlled by the injector’s tip design. There are three different types of tips; pintle (needle and seat), ball and seat and disc style. Once the manufacturer has chosen which style of injector to use it should not be changed in the field.

A spray pattern that does not match the OE injector’s spray pattern can cause driveability symptoms, higher emissions, starting problems and poor fuel economy. For example, an injector that has a narrow well atomized spray pattern (pintle) is replaced by a technician with a disc style injector that may have a wider spray pattern. This can result in fuel contacting the sides of the cylinder head just above the intake valve. This can cause the fuel to puddle, resulting in poor driveability and higher emissions. If the technician were only to replace a single injector rather than an entire set it can result in poor idle quality because of the variation in spray patterns between cylinders.

One of the greatest areas of concern with aftermarket new injectors is the fact that some aftermarket manufacturers are substituting injectors that have a different spray pattern than their OEM counterpart. The real down side to this is that it is impossible for the technician to determine this simply by looking at the part and comparing it to the one they are replacing. Unless the technician has a method to flow test the injector and visually inspect the spray pattern they won’t know. An aftermarket new injector may have a “good” spray pattern that is well atomized but might not be suitable for a particular vehicle application it is being sold for.  It is highly unlikely that the aftermarket manufacturer conducted testing on their new universal injector in every vehicle it is being sold for. Instead, they compromise on the spray pattern specification in order to achieve the least possible part numbers which cover the most vehicles.

Injector Flow Rate

Injector flow rate is the amount of fuel the injector will deliver over a specified period of time. This is usually expressed as cubic centimeters per minute (cc/min) or pounds per hour (lbs/hr). Even OEM injectors have an acceptable tolerance for this specification to allow for tiny variations in manufacturing processes. But these tolerances are extremely tight.

Unfortunately OE manufacturers do not publish injector flow specifications. However, the absence of such specifications does not constitute a legitimate reason for an aftermarket company to provide sub-standard parts.

Accurate specifications are obtained by testing numerous new OEM injectors to document the injectors flow rate and tolerances. GB has the industry’s most extensive test database of injectors consisting of over 1,000 unique OEM part numbers. It took years of testing, research and development to acquire this knowledge but it is critical in delivering injectors that meet OEM specifications.

Many aftermarket new injectors may meet the flow specification for some of the OEM part numbers it is replacing. Although, it is very common that the vast majority of the other applications for the part number has a flow that is too high or low.  Again, this is the byproduct of part consolidation.

Electrical Specifications

The electrical specifications of the injector include the injector’s coil resistance. This is determined by the type of the wire used and the length of the wire in the injector’s coil and is critical for proper operation. When the PCM activates the injector a magnetic field is created within the injector, the injector opens allowing fuel to be injected into the engine. The coil has a direct influence on the opening time of the injector which will affect the injector’s dynamic flow rate. An injector that has a lower coil resistance will result in an injector that opens faster than an injector with a higher coil resistance.

The vehicle manufacturer has chosen the proper injector for their application and this has been accounted for within the vehicles PCM. Replacing an injector out in the field with one that does not have the identical coil resistance can result in variations in dynamic flow rates. This is especially true if only a few out of an entire set are replaced with new consolidated aftermarket type injectors.

Mechanical/Cosmetic Specifications

Another area of concern regarding aftermarket new injectors is in some cases the injector’s physical appearance does not match its OE equivalent. GB has seen aftermarket new injectors where the body of the injector, plastic color and exterior dimensions do not match the OEM injector. 

With some aftermarket parts their appearance may not match the OEM part and in some cases this might be acceptable. However, given the precision and tight tolerance injectors have it should be a red flag that the replacement part may not meet other critical OEM specifications.

Part Consolidation

Certain part categories are not good candidates for aftermarket new replacement parts. This is especially true when there are a large number of part numbers (SKUs), high technological content that includes parts with extremely tight tolerances or parts that require extremely specialized manufacturing capabilities. Fuel injectors fall into this category. The sheer number of part numbers and the precision tolerances of the internal fuel metering parts make manufacturing a complete line of new fuel injectors impractical from an economic standpoint.

Some aftermarket companies have attempted to provide injectors that can be manufactured in high volumes that are “universal” and fit numerous applications. With fuel injectors this results in a one size – fits none program. Fuel injectors are not thermostat gaskets and shouldn’t be treated as such!

From a cost standpoint new OEM injectors are an expensive proposition for an older vehicle, especially considering the cost of an entire set. New aftermarket injectors are also more expensive than GB’s remanufactured injectors and may not meet OEM specifications. The advantage is that GB’s remanufactured injectors are a perfect fit for the market. They are remanufactured OEM injectors that meet all OEM specifications at a lower cost than either new OEM or new aftermarket injectors.

The technician can have complete confidence that every part that comes in a GB box looks, fits and functions just like the original equipment injector because it is an OE injector.

Ford 7.3L Powerstroke IDM Operation

The Ford Power Stroke 7.3L engine has established its legacy as a reliable and stout diesel engine. Over two million of the engines were produced from 1994 through 2003. It was replaced with the 6.0L Power Stroke engine in 2003 because it could not meet new federal emission standards.

Because of their proven track record as being a solid long lasting engine the repair market for these engines is quite healthy. As with any high production vehicle, problems can and will occur. One area for potential repairs is the Injector Driver Module, or “IDM”.

The 7.3L utilizes Hydraulically actuated Electronically controlled Unit Injectors, commonly referred to as HEUI or “HUEY” injectors. These injectors utilize high pressure oil which is controlled by a poppet valve inside the injector to achieve injection pressures of up to 21,000 psi. The poppet valve operation is electronically controlled by an injector mounted solenoid.

Because of the high pressures involved, the solenoid-operated poppet valve requires 115 volts at up to 8 amps to operate, which is more power than the Powertrain Control Module (PCM) can provide. Because of this, the injectors are directly controlled by a separate control module called the Injector Driver Module (IDM). The IDM provides the high voltage and switching signals to turn the injectors on and off.

The IDM and PCM work together to control the entire fuel system (see system diagram on facing page for call outs). The PCM receives inputs from numerous sensors then transmits injection timing signals to the IDM module, which then carries out the activation of the injectors.

Injector Power & Ground

The injectors are grouped into two banks of four injectors each. Each bank shares a common power feed which is generated by the IDM. The voltage supplied to the injectors is 115 volts DC and is only activated when one of the injectors is firing.

The injectors have 8 individual ground circuits. An injection event occurs when the IDM supplies power to the bank for the injector to be fired while simultaneously grounding the desired injector’s ground circuit. The pulse supplied to the solenoid is typically between .5-2.0 milliseconds.

Injection Fuel Volume

Unlike gasoline injectors or other electronically controlled diesel injectors, the fuel volume is not controlled by the pulse width that is supplied to the injector. Instead, fuel volume is controlled by the oil pressure supplied to the injector, referred to as the Injection Control Pressure (ICP).

Oil pressure is supplied to the injector by a mechanically driven injection pump (A) at pressures of up to 3,000 psi. The injector is also supplied fuel at approximately 40-50 psi (B). Separation between the fuel and oil is accomplished with internal and external o-rings.

When the solenoid is activated the high pressure oil is supplied to the top of an internal intensifier piston, which acts upon a fuel plunger causing the fuel to be injected. The intensifier piston has an area that is seven times larger than the fuel plunger. Because of this, the pressure on the plunger is amplified to achieve injection pressures of up to 21,000 psi.

The Injection Control Pressure (ICP) is closed-looped controlled by the PCM. The PCM monitors the ICP Sensor (C) and modulates the ICP Regulator (D) to achieve the desired control pressure for the current operating condition. The fuel volume injected is directly proportional to the injection control pressure. The PCM monitors numerous input sensors to calculate the fuel demand including the Accelerator Pedal Position sensor, Engine Coolant Temperature sensor and Manifold Absolute Pressure to name a few.

Injection Timing and Synchronization

In order for the IDM to synchronize the injection events to crankshaft position it must communicate with the PCM.

The PCM generates two digital control signals for the IDM: the Fuel Delivery Control Signal  (F) and the Cylinder Identification (G).  The FDCS signal is used by the IDM to control injection timing and duration. The CID signal provides synchronization to the engine’s first and fifth injector.

Cylinder Identification Signal (CID)

The PCM receives engine rotational position information from the Camshaft Position  sensor (CMP). The CMP (E) is a hall-effect device. It outputs 12 volts to the PCM whenever it detects the iron of a spoke on the target wheel in front of it. It outputs 0 volts whenever it detects the space between the spokes. The target wheel spokes and spaces are each 15 crank degrees apart, except for narrow spoke which indicates cylinder number 1 and a wide spoke which indicates cylinder number 4 (fifth in firing order).

The PCM receives the Camshaft Position signal and transmits a modified signal (G) to the IDM that indicates which injector bank should be firing. Bank 1 consisting of cylinders 1, 3, 5 and 7 is located on the passenger side while bank 2 consisting of cylinders 2, 4, 6 and 8 is located on the driver’s side. The IDM uses this signal to determine which high side driver should be switched on.

Fuel Delivery Control Signal (FDCS)

Actual injector timing and duration is controlled by the Fuel Delivery Controlled Signal. The PCM generates and transmits a pulse for each injection event (F) to the IDM. The IDM uses this signal to turn on the proper low side driver for the injector being activated.

The IDM is programmed with the firing order of the vehicle. Using both the CID and FDC signals from the PCM the IDM provides precise synchronization of injection events to piston position.

Self Diagnostics

The IDM monitors the injector switching circuits and can transmit diagnostic information to the PCM if it detects a fault (H). The PCM will store a Diagnostic Trouble Code (DTC) specific to the type of failure, which can be retrieved using the appropriate diagnostic equipment. There are numerous diagnostic codes related to the IDM so consult the vehicle specific service information for a definition of each code.

Failure Modes

The IDM module is mounted in the engine compartment and due to its location is very susceptible to water damage. Water intrusion takes place through an air vent that is an integral part of the IDM case. Once water enters the module, failure is eminent and usually results in a no-start condition. On units remanufactured by GB the vent has been redesigned to prevent this type of failure.

Another failure mode is the result of failed wiring between the IDM and the injectors. The fuel injectors on the 7.3L are located under the valve covers. Because of this, the wires for each bank of injectors pass through connectors that are molded into the valve cover gaskets. The wiring on the inside of the valve covers are constantly exposed to hot oil. Over time these connectors can become brittle and crack causing the wires to short together causing IDM failure. This type of failure must be diagnosed PRIOR to replacing the IDM; otherwise failure of the replacement module will result. Additionally, these poor connections can be intermittent so a visual inspection and electrical test is recommended prior to condemning or replacing an IDM. Intermittent connections can be difficult to diagnose and can result in intermittent injector fire either on a single injector or an entire bank. Failure to locate this type of failure can result in costly warranty come-backs. In order to properly inspect the wiring to the injectors the valve covers should be removed. It is a best practice to replace the valve cover gaskets when reinstalled if they are the original gaskets.

GB has published Tech Bulletin TB#103 that details the tests that should be performed prior to replacement.

Replacement Tips and Warnings

The actual replacement of the IDM is not technically challenging, however proper diagnosis to eliminate damage to the new IDM is critical. Here are some tips that can help:

Check for Diagnostic Trouble Codes (DTC). Follow the appropriate service manual tests for each DTC retrieved.
Perform a thorough visual inspection on the wiring between the IDM and the injectors. Flexing and wiggling the wiring harness can detect some faults and should be performed during the pin point test detailed in TB# 103.
Inspect the connectors at the valve cover gaskets both on the inside and outside. Make sure the connectors, wires and seals are not broken or soft.
Inspect the outside of the IDM. If there is corrosion present or the paint is peeling off, chances are the IDM has internal water damage. If the aluminum vent cover is missing then water damage is highly probable.
Use caution when working on the IDM system. High voltage is present on the injector wires when the engine is running (115 volts). These wires are shielded and piercing the wires will result in wiring harness damage not to mention personal injury.

Application Information

GB offers two part numbers to cover all 7.3L Power Stroke applications from 1994 through 2003. 1994-98 model years use part number 921-110 while 1999-2003 utilize GB part number 921-120. Another quick way to identify the IDM is by color. If the OE module is silver or bare aluminum it is the early module (921-110) while the 921-120 version is black.

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