Poor Idle Quality

FAULT INDICATIONS
Idle speed uneven, too high, or too low

FAULT TRACING CONDITIONS
Before fault tracing, ensure that:
^ No diagnostic trouble codes are present
^ The engine is at operating temperature, and
^ All fuses are clean and intact

UNEVEN IDLE SPEED
^ Blocked injectors
^ Faulty sensor signals

IDLE SPEED TOO HIGH
^ Intake air leakage
^ Faulty idle air control valve

IDLE SPEED TOO LOW
^ Throttle Plate incorrectly adjusted
^ Faulty idle air control valve