Shutter Valve
WARNING: This page is about a different car, the 1994 Mazda 929. However, it is still accessible from the selected car via links, so may be relevant.
Shutter valve stopper bolt is preset at factory. DO NOT adjust shutter valve stopper bolt. Remove shutter valve actuator. Ensure shutter valve rotates smoothly. See Fig 1 . Replace dynamic chamber if valve is stuck or does not rotate smoothly.