*LACK OF ENGINE POWER

For a complete wiring diagram Refer to Section 8W



Possible Causes
AIR IN FUEL SYSTEM
FUEL INJECTOR CLASSIFICATION
INTAKE/EXHAUST SYSTEM RESTRICTION
EGR SYSTEM PROBLEM
LOW ENGINE COMPRESSION
INTAKE AIR SYSTEM LEAK
FUEL DELIVERY SYSTEM RESTRICTION
ENGINE DRIVE BELT/CHAIN
FUEL INJECTOR(S)
FUEL PRESSURE SOLENOID
FUEL INJECTION PUMP
FUEL SYSTEM CONTAMINATION
FUEL SYSTEM LEAK
TURBOCHARGER



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


No

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


No

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


No

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


No

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


No

6. FUEL INJECTOR CLASSIFICATION

NOTE: Each Fuel Injector is labeled with a code. This code determines the injector classification. Each Injector classification 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 classification for each fuel injector in the ECM.

Are all of the injectors classified correctly?

Yes


No

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


No

8. FUEL INJECTOR

NOTE: An injector that sticks open can cause this symptom. A sticking injector will cause the engine to misfire 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


No

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


No

10. CHECKING THE SUPPLY SIDE FUEL DELIVERY SYSTEM

Refer to the Checking the Low Pressure Fuel Delivery System Test 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


No

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 (7.0 bar) 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


No

12. FUEL PRESSURE SOLENOID

Turn the ignition off.
Replace the Fuel Pressure Solenoid in accordance with the Service Information.
Test drive the vehicle.

Does the vehicle still exhibit a lack of power?

Yes


No

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 Charge Air Cooler hoses/tubes and connections.
Inspect the air filter for excessive dirt, soiling or other problems that may cause restricted air flow.

Were any problems found?

Yes


No

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


No

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


No