Air Control Valve
- Verify that air is being supplied to valve inlet by disconnecting inlet supply hose. Disconnect hose at valve outlet and hose from vacuum nipple. Some air flow should be heard and felt at valve outlet with engine at 1500 RPM.
- Using a direct vacuum line from manifold vacuum source, connect line to vacuum nipple. An increase in air flow should be detected when vacuum is applied. If valve fails any test, replace valve. Reconnect all lines.