Stalls/Rough, Unstable or Incorrect Idle

Definition: 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

Poor or contaminated fuel Drain fuel tank and fill with clean gasoline

Incorrect air/fuel ratio Check computer control system

Incorrect fuel pressure Correct as needed

Incorrect idle speed Check and adjust