Shutter Valve Actuator
WARNING: This page is about a different car, the 1995 Mazda 929. However, it is still accessible from the selected car via links, so may be relevant.
Disconnect vacuum hose from shutter valve actuator. See Figure . Connect vacuum pump to actuator. If rod does not move disconnect rod and check rod and valve for freedom of movement. Apply vacuum and verify shutter valve rod retracts. Replace as necessary. DO NOT adjust shutter valve stopper bolt.