Vacuum Motor
WARNING: This page is about a different car, the 1989 Nissan 240SX. However, it is still accessible from the selected car via links, so may be relevant.
Disconnect inlet vacuum hose at vacuum motor. Connect vacuum pump hose at inlet. Apply 2.95 in. Hg, air control valve should start to open. Apply 6.50 in. Hg, air control valve should fully open. If air control valve does not operate as specified, replace air control valve.