Idle Speed Air Control Valve (ISACV)

1. Open the hood.

2. Note:
Key symptom is elevated idle speed while noise is occurring.

Note:
"Snapping" the throttle can induce the noise.

Verify the condition by operating the vehicle for a short time.

3. Inspect the ISACV. If physical evidence of contamination exists, install a new ISACV.

4. While the noise is occurring, either place an EngineEAR probe near the ISACV 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 ISACV is making the noise, install a new ISACV.

5. Test the vehicle for normal operation.