Common Symptoms
- Engine idle speed is too high or unstable
- Check Engine Light is illuminated
- Engine stalls when coming to a stop
- Rough or erratic idle condition
- Difficulty starting the engine
Most Likely Root Causes
- Faulty idle air control valve or motor
- Carbon buildup on throttle body or idle air passages
- Damaged or corroded wiring harness to idle control valve
- Vacuum leak in intake system
- Faulty engine control module
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Component Location
The idle air control valve is typically mounted on or near the throttle body assembly on the intake manifold.
Manufacturer Notes
Some manufacturers recommend cleaning the throttle body and idle air passages as a first step before replacing the idle air control valve.
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