Auxiliary Air Valve System: 3.0L
- Install tachometer. With engine coolant temperature less than 176°F (80°C), start engine.
- With engine idling, turn idle speed adjusting screw inward to bottom of bore while counting number of revolutions. See Fig 1. Engine speed should decrease noticeably.
- Return idle speed adjusting screw to original position. Warm engine to normal operating temperature. Repeat step 2). Engine speed should not change or should drop slightly.
- If engine RPM does not respond as indicated, check for vacuum leaks or restricted auxiliary air valve circuit. If no defects are found, replace auxiliary air valve, located on bottom of valve body.
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