GM Service Manual Online
For 1990-2009 cars only

Inspection

Action

DEFINITION: Engine continues to run after key is turned OFF, but runs very rough. If the engine runs smooth, check the ignition and adjustment.

Fuel System

    • Test the fuel system for excessive fuel pressure. Refer to Fuel System Diagnosis .
    • Test for leaking fuel injectors. Refer to Fuel Injector Diagnosis .
    •  Inspect for carbon build up or other hot point within the combustion chamber.
    • Inspect the intake and exhaust system and associated passages for casting flash.

Ignition System

    • Inspect for proper ignition system operation. Refer to Electronic Ignition (EI) System Diagnosis .
    • Inspect the spark plugs. Refer to Spark Plug Inspection .
    • Inspect for correct base ignition timing.
    • Inspect the spark plugs for correct application. Refer to Ignition System Specifications .

Additional Inspections

    •  Inspect for carbon buildup or other hot point within the combustion chamber.
    • Inspect the intake and exhaust system and associated passages for casting flash.