Diagnostic Inspection

DIAGNOSTIC INSPECTION

Refer to section EC in the Service Manual under "P0300, P0301, P0302, P0303, P0304 MISFIRE" for details on the following inspection items.

1. Check operation of ignition coils and spark plugs.

2. Check fuel pressure.

3. Check fuel quality and condition make sure diesel fuel has not been introduced into the fuel tank.

4. Check intake air leaks and PCV hose connections.

5. Check function of fuel injectors - listen to each fuel injector operating sound.

6. Check MASS AIR FLOW SENSOR.

7. Check A/F SENSOR.

8. Check idle speed and ignition timing.

9. Check items under "ROUGH IDLE/HUNTING" in the symptom chart.

^ Symptom chart is located in Section EC under SYMPTOM DIAGNOSIS.

10. Some tests may cause a 1st trip DTC to be set - erase any 1st trip DTCs from the ECM.

11. Check exhaust system for dents that would restrict exhaust flow.