Idle Air Control (IAC) Valve

1. Open the hood.
2. Verify the condition by operating the vehicle for a short time.

NOTE:
^ Key symptom is elevated idle speed while noise is occurring.
^ "Snapping" the throttle can induce the noise.

3. Inspect the IAC valve. If physical evidence of contamination exists, install a new IAC valve.
4. While the noise is occurring, either place an EngineEAR probe near the IAC valve and the inlet tube, or create a 6.35 mm (0.25 in)-12.7 mm (0.50 in) air gap between the inlet tube and the clean air tube. If the IAC valve is making the noise, install a new IAC valve.
5. Test the vehicle for normal operation.