Diagnostic Test
| Possible Causes |
|---|
| FAULTY AFTERTREATMENT SYSTEM |
| OUTDATED ECM/PCM CALIBRATION |
| POOR FUEL QUALITY/CONTAMINATION |
| AIR FILTER RESTRICTION |
| LEAK IN THE INTAKE AIR SYSTEM |
| EXHAUST SYSTEM LEAKS/RESTRICTIONS |
| FAULTY FUEL INJECTOR |
| FUEL SYSTEM ISSUES |
- CHECK TSBs NOTE:
This vehicle is equipped with a Diesel Particulate Filter (DPF) which should trap most particles that would appear out of the tail pipe in the form of black or blue smoke. If black or blue smoke is coming from the tail pipe, the DPF should be inspected for damage after the root cause of the problem is diagnosed and corrected.
- With the scan tool, check for any TSBs that may apply.
Were there any TSBs that applied to and repaired the condition?
Yes
- Perform the appropriate repair.
- Perform the AFTERTREATMENT INSPECTION GUIDELINE procedure. Refer to AFTERTREATMENT INSPECTION GUIDELINE .
No
- Go To 2.
- With the scan tool, check for any TSBs that may apply.
- CHECK FUEL FOR CONTAMINATION
- Perform the DIESEL FUEL CONTAMINATION AND CLEANING PROCEDURE. Refer to DIESEL FUEL CONTAMINATION TESTING PROCEDURE
, and DIESEL FUEL SYSTEM CLEANING PROCEDURE
.
Is the fuel contaminated with debris?
Yes
- Follow step three of the DIESEL FUEL CONTAMINATION AND CLEANING PROCEDURE and clean the diesel fuel system and Fuel Injectors.
- Perform the AFTERTREATMENT INSPECTION GUIDELINE procedure. Refer to AFTERTREATMENT INSPECTION GUIDELINE .
No
- Go To 3.
- Perform the DIESEL FUEL CONTAMINATION AND CLEANING PROCEDURE. Refer to DIESEL FUEL CONTAMINATION TESTING PROCEDURE
, and DIESEL FUEL SYSTEM CLEANING PROCEDURE
.
- CHECKING CYLINDER CONTRIBUTION
- Using the scan tool, navigate to Miscellaneous Functions perform the Fuel System Run Up test procedure.NOTE:
This test will take approximately 270 seconds to complete. The PCM will cut out each individual Fuel Injector three times and calculate the delta RPM change. Based on the delta RPM change, the test will indicate a bad cylinder based on the limits that have been set. When the test is complete, the engine will return to idle.
Do the results indicate that a cylinder is out of spec?
Yes
- Refer to the CHECKING ENGINE MISFIRE / RUNS ROUGH / PERFORMANCE TEST and begin at 5 for diagnosing a single cylinder issue.
No
- Go To 4.
- Using the scan tool, navigate to Miscellaneous Functions perform the Fuel System Run Up test procedure.
- CHECK THE FUEL DELIVERY SYSTEM
- Perform the CHECKING THE FUEL DELIVERY SYSTEM test procedure. Refer to CHECKING THE FUEL DELIVERY SYSTEM .
Were any problems found?
Yes
- Perform the appropriate repair.
- Perform the AFTERTREATMENT INSPECTION GUIDELINE procedure. Refer to AFTERTREATMENT INSPECTION GUIDELINE .
No
- Refer to the CHECKING ENGINE MISFIRE / RUNS ROUGH / PERFORMANCE TEST and begin at test step 8.
- Perform the CHECKING THE FUEL DELIVERY SYSTEM test procedure. Refer to CHECKING THE FUEL DELIVERY SYSTEM .