Air Control Valve
- Warm engine to normal operating temperature. Stop engine and disconnect outlet hose from bottom of air control valve. Start engine and run at idle speed.
- Disconnect vacuum hose from No. 1 relief valve. Air should be discharged from outlet port. Reconnect vacuum hose. Air should not be discharged from outlet port.
- Disconnect and plug No. 2 relief valve vacuum hose from air control valve. Using a "T" fitting and additional tubing, install "T" between intake manifold and evaporative shutter valve.
- Connect additional tubing to "T" and No. 2 relief valve so intake manifold vacuum is applied directly to No. 2 relief valve. Air should be discharged from air control valve outlet port.
- Disconnect and plug vacuum hose at No. 2 relief valve. Air should not be discharged from air control valve outlet port. If air control valve does not respond as described, replace air control valve.