Poor Idle Quality
FAULT INDICATIONSIdle 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, Fuel Injector
^ Faulty sensor signals, Computers and Control Systems
IDLE SPEED TOO HIGH
^ Intake air leakage
^ Faulty idle air control valve, Computers and Control Systems
IDLE SPEED TOO LOW
^ Throttle Plate incorrectly adjusted, Throttle Plate - PFI
^ Faulty idle air control valve, Computers and Control Systems