Actuator Test
WARNING: This page is about a different car, the 2001 Mitsubishi Eclipse. However, it is still accessible from the selected car via links, so may be relevant.
Disconnect vacuum hose and connect hand vacuum pump. Apply vacuum to actuator. Actuator linkage holder should move and actuator diaphragm should hold vacuum. If linkage does not move, or vacuum does not hold, replace vacuum actuator.