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Air Supply Control Valve

  1. Disconnect air supply hose at inlet. Accelerate engine to 1500 RPM and verify presence of airflow in hose. Reconnect air supply hose to valve inlet.
  2. Disconnect air supply hoses at outlets "A" and "B". See Fig 1 . Remove vacuum line at vacuum nipple. Accelerate engine to 1500 RPM. Airflow should be heard and felt at outlet "B" with little or no airflow at outlet "A".
  3. Connect a vacuum line from manifold vacuum fitting to air supply control valve vacuum nipple. Accelerate engine to 1500 RPM. Airflow should be heard and felt at outlet "A" with little or no airflow at outlet "B".
  4. If valve does not meet above conditions, replace valve. If airflow operates as described in steps 1 - 3, valve is okay. Reinstall hoses and clamps.
Fig 1: Air Supply Control Valve
G90F14329Courtesy of FORD MOTOR CO.