Navigator 4WD V8-5.4L DOHC VIN A (2000)
Idle Air Control Valve: Testing and Inspection
Idle Air Control (IAC) Valve Check
1. Open the hood.
2. Verify the condition by operating the vehicle for a short time.
NOTE:
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Key symptom is elevated idle speed while noise is occurring.
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"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.