Diagnostic Aids
Inspect for the following conditions:
- Skewed high TP sensor.
- Restricted air intake system.
- Objects blocking IAC passage or throttle bore.
- Correct Positive Crankcase Ventilation (PCV) valve, properly installed and proper operation of PCV valve (if equipped).
- Proper operation and installation of all air intake components.
- Proper installation and operation of Mass Air Flow (MAF) sensor (if equipped).
- Tampered with or damaged throttle stop screw.
- Tampered with or damaged throttle plate, throttle shaft, throttle linkage, or cruise control linkage (if equipped).
- Excessive deposits in IAC passage or on IAC pintle.
- Excessive deposits in throttle bore or on throttle plate.
- Vacuum leaks
- Excessive engine load caused by faulty transmission, power steering, alternator, etc.
- High or unstable idle condition caused by a non-IAC system problem that can not be overcome by IAC valve.
- Low or unstable idle condition caused by a non-IAC system problem that can not be overcome by IAC valve.