Common Symptoms
- Engine idle speed fluctuates or surges
- Engine stalls at idle or when coming to a stop
- Idle speed too high or too low
- Check Engine Light illuminated
- Rough or unstable idle when engine is warm
- Difficulty starting after engine is warm
Most Likely Root Causes
- Failed or sticking idle air control valve
- Carbon buildup on throttle body or idle control valve
- Vacuum leak in intake manifold or hoses
- Faulty throttle position sensor
- Dirty or restricted air filter
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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 periodic throttle body cleaning as preventive maintenance to avoid idle control issues.
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