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Auxiliary Air Valve System (2.4L)

  1. With engine coolant less than 176°F (80°C), install tachometer. See ADJUSTMENTS article in the ENGINE PERFORMANCE Section for tachometer attaching points.
  2. Start engine. With engine idling, turn idle speed adjusting screw to bottom of bore while counting number of revolutions. Engine speed should drop noticeably.
  3. Return idle adjusting screw to original position. Warm engine to normal operating temperature. Repeat step 2). Engine speed should not change or should drop slightly.
  4. If engine RPM does not respond as indicated, check for vacuum leaks after the valve or restricted chamber in auxiliary air valve circuit. If no defects are found, replace auxiliary air valve.
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