Manual Transmission Equipped Models

Detach air hose from bottom of air control valve. Start and run engine at idle. Remove vacuum line from air by-pass valve.
Air should come from bottom outlet of air control valve. Plug disconnected vacuum line. No air should flow from bottom outlet of valve.
Remove intake manifold vacuum line from relief valve on side of air control valve. Unplug by-pass valve vacuum line and connect this line to nipple on side of relief valve from which intake manifold vacuum line was removed.
Air should now come from bottom outlet of air control valve. If valve does not respond as indicated, check vacuum lines. If okay, replace air control valve.