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Lack Of Engine Power







*LACK OF ENGINE POWER

For a complete wiring diagram Consult Diagrams/Electrical





Diagnostic Test

1. CHECKING FOR ECM DTCS

WARNING: HIGH-PRESSURE FUEL LINES DELIVER DIESEL FUEL UNDER EXTREME PRESSURE FROM THE INJECTION PUMP TO THE FUEL INJECTORS. THIS MAY BE AS HIGH AS 23,200 PSI (1600 BAR). USE EXTREME CAUTION WHEN INSPECTING FOR HIGH-PRESSURE FUEL LEAKS.

WARNING: FUEL UNDER THIS AMOUNT OF PRESSURE CAN PENETRATE SKIN CAUSING PERSONAL INJURY OR DEATH. INSPECT FOR HIGH-PRESSURE FUEL LEAKS WITH A SHEET OF CARDBOARD. WEAR SAFETY GOGGLES AND ADEQUATE PROTECTIVE CLOTHING WHEN SERVICING FUEL SYSTEM.

Turn the ignition on.
With the scan tool, read the ECM DTCs.
Are there any DTCs present?

Yes

- Refer to symptom list for problems related to this DTC.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Go To 2

2. FUEL SYSTEM LEAK
Turn the ignition off.

WARNING: HIGH-PRESSURE FUEL LINES DELIVER DIESEL FUEL UNDER EXTREME PRESSURE FROM THE INJECTION PUMP TO THE FUEL INJECTORS. THIS MAY BE AS HIGH AS 23,200 PSI (1600 BAR). USE EXTREME CAUTION WHEN INSPECTING FOR HIGH-PRESSURE FUEL LEAKS.

WARNING: FUEL UNDER THIS AMOUNT OF PRESSURE CAN PENETRATE SKIN CAUSING PERSONAL INJURY OR DEATH. INSPECT FOR HIGH-PRESSURE FUEL LEAKS WITH A SHEET OF CARDBOARD. WEAR SAFETY GOGGLES AND ADEQUATE PROTECTIVE CLOTHING WHEN SERVICING FUEL SYSTEM.

Inspect the entire fuel system for leakage.
Is there any evidence of leakage?

Yes

- Repair as necessary.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Go To 3

3. FUEL SYSTEM CONTAMINATION

NOTE: Mixing any other fuels such as gasoline or kerosine can cause this symptom to occur.

Turn the ignition off.

WARNING: HIGH-PRESSURE FUEL LINES DELIVER DIESEL FUEL UNDER EXTREME PRESSURE FROM THE INJECTION PUMP TO THE FUEL INJECTORS. THIS MAY BE AS HIGH AS 23,200 PSI (1600 BAR). USE EXTREME CAUTION WHEN INSPECTING FOR HIGH-PRESSURE FUEL LEAKS.

WARNING: FUEL UNDER THIS AMOUNT OF PRESSURE CAN PENETRATE SKIN CAUSING PERSONAL INJURY OR DEATH. INSPECT FOR HIGH-PRESSURE FUEL LEAKS WITH A SHEET OF CARDBOARD. WEAR SAFETY GOGGLES AND ADEQUATE PROTECTIVE CLOTHING WHEN SERVICING FUEL SYSTEM.

Inspect the fuel system for contamination.
Is the fuel contaminated?

Yes

- Repair as necessary.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Go To 4

4. CHECKING BOOST PRESSURE
Turn the ignition on.

NOTE: This test requires two people. One person to test drive the vehicle while a technician observes the scan tool readings

With the scan tool in Sensors, read and compare the Boost Pressure (PSI) with the Boost Pressure Desired/Setpoint (PSI) while test driving the vehicle under various load conditions such as idle, hard acceleration, and cruise.

NOTE: The Boost Pressure reading should directionally follow (trail) the Boost Pressure Desired/Setpoint reading.

Does the Boost Pressure reading follow the Boost Pressure Desired/Setpoint reading?

Yes

- Go To 5

No

- Go To 13

5. CHECKING FUEL PRESSURE
Turn the ignition on.

NOTE: This test requires two people. One person to test drive the vehicle while a technician observes the scan tool readings

With the scan tool in Sensors, read and compare the Fuel Pressure (PSI) with the Fuel Pressure Desired/Setpoint (PSI) while test driving the vehicle under various load conditions such as idle, hard acceleration, cruise and deceleration.

NOTE: The Fuel Pressure reading should directionally follow (trail) the Fuel Pressure Desired/Setpoint reading.

Does the Fuel Pressure reading directionally follow the Fuel Pressure Desired/Setpoint reading?

Yes

- Go To 6

No

- Go To 10

6. INJECTOR QUANTITY ADJUSTMENT

NOTE: Each Fuel Injector is labeled with a code. This code determines the injector quantity adjustment. Each Injector code must be programmed into the ECM using the scan tool.

Turn the ignition off.
Refer to the service information to locate each fuel injector label and check for the correct code for each fuel injector in the ECM.
Are all of the injector codes correct?

Yes

- Go To 7

No

- Using the scan tool, program the correct Fuel Injector code into the ECM.
- Perform the ECM Verification Test Ver. 1. Verification Tests

7. ENGINE COMPRESSION
Start and idle the engine.
With the scan tool, perform the Cylinder Compression Test.
Does the Cylinder Compression Test indicate low compression in any of the cylinders?

Yes

- Repair the engine as necessary to regain proper cylinder compression.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Go To 8

8. FUEL INJECTOR

NOTE: An injector that sticks open can cause this symptom. A sticking injector will cause the engine to miss fire and emit excessive black smoke from the exhaust system.

Start and idle the engine.
With the scan tool, perform the Cylinder Fuel Quantity Correction Test.

NOTE: A problem injector will be indicated by a significant change in correction quantity as compared to the rest of the injectors.

Are any of the injectors displaying a significant amount of injection quantity correction?

Yes

- Remove and inspect the Fuel Injectors for signs of damage or debris that may cause the injector to stick. Sticking injectors may cause the combustion chamber to become black and oil soaked. Replace Injector(s) as necessary.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Go To 9

9. ENGINE DRIVE BELT/CHAIN
Refer to the service information to ensure the Engine Drive Belt/Chain is installed correctly and the camshaft and crankshaft gears are timed correctly.
Were any problems found?

Yes

- Repair as necessary.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Test Complete.

10. CHECKING THE SUPPLY SIDE FUEL DELIVERY SYSTEM
Refer to the appropriate service information and test for proper Fuel pressure and volume from the fuel tank to the high pressure Fuel Injection Pump.

NOTE: The following is a list of problems that can cause fuel pressure to deviate from specification: restricted fuel filter or fuel lines, air in fuel system, failed fuel sending unit, contaminated fuel.

Were there any problems with the Fuel Delivery System?

Yes

- Repair as necessary.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Go To 11

11. CHECKING FOR AIR IN FUEL SYSTEM
Start the engine.
With the scan tool in Sensors, compare the Fuel Pressure Setpoint with the Actual Fuel Pressure readings.

NOTE: If there is air in the fuel system, the Actual Fuel Pressure will oscillate more than 100 psi above and/or below the Fuel Pressure Setpoint.

Does Actual Fuel Pressure oscillate more than 100 psi (7.0 bar) above and/or below the Fuel Pressure Setpoint?

Yes

- Purge air from the fuel system.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Go To 12

12. FUEL PRESSURE SOLENOID
Turn the ignition off.
Replace the Fuel Pressure Solenoid.
Turn the ignition on.
With the scan tool, erase the ECM DTCs.
Attempt to start and test drive the vehicle.
With the scan tool, read the ECM DTCs.
Does the ECM display this DTC?

Yes

- Replace the Fuel Injection Pump assembly.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Test Complete.

13. CHECK FOR INTAKE AND EXHAUST SYSTEM RESTRICTIONS
Turn the ignition off.
Inspect the exhaust system for damaged components that could cause exhaust flow blockage.
Inspect all air intake, crankcase vent and turbocharger related hoses/tubes and connections for damage, air leaks or blockage.
Inspect the air filter for excessive dirt, soiling or other problems that may cause restricted air flow.
Were any problems found?

Yes

- Repair or replace as necessary.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Go to 14

14. CHECKING FOR AIR LEAKS

NOTE: Inspect all air intake and turbocharger related tubes for damage, restriction or poor connection. Any of these conditions can cause a poor performance/lack of power symptom.

Turn the ignition off.
Remove the Crankcase Vent Heater.
Remove the Mass Air Flow Sensor from the turbocharger inlet tube.
Seal off and/or plug the turbocharger inlet tube where the MAF sensor was removed.
Connect smoke machine 84-04 to the Crankcase Vent Heater port in the intake duct and begin injecting smoke into the intake system.
Observe all intake system components for evidence of smoke leakage.
Is there evidence of smoke leakage?

Yes

- Repair or replace as necessary.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Go To 15

15. EGR SYSTEM
Refer to the symptom list and perform the CHECKING THE EGR SYSTEM test.
Were any problems found during the EGR System test?

Yes

- Repair or replace as necessary.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Check for proper linkage connection between the Boost Pressure Servo Motor and the Turbocharger assembly. Repair or replace as necessary. If o.k., replace the Turbocharger assembly.

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