Pressure Regulator Control Solenoid
WARNING: This page is about a different car, the 1995 Mazda Millenia. However, it is still accessible from the selected car via links, so may be relevant.
Disconnect vacuum hose from pressure regulator control solenoid. Blow air through solenoid port "A". See Fig 1 . Ensure air flows through port "B". Disconnect solenoid valve electrical connector. Connect 12 volts and ground to solenoid terminals. Blow air through solenoid port "A". Air should flow through valve air filter. Replace solenoid as necessary.