Rough/Unstable Idle or Stalling

SYMPTOM DESCRIPTION:

The engine runs unevenly at idle. If bad enough, the vehicle may shake. Also, the idle may vary in RPM. Either condition may be severe enough to cause stalling. Engine idles at incorrect speed.


POSSIBLE CAUSE ACTION



Throttle linkage sticking/binding ^ Check and adjust throttle linkage and cable.


Incorrect air/fuel mixture ^ Check air/fuel ratio (02 sensor voltage). SEE Computers and Control Systems.

^ Perform injector balance test.

^ Check fuel pressure (check return hose).


Incorrect idle speed ^ Check and clean throttle body.