Checking Vacuum Valve In Cap
WARNING: This page is about a different car, the 2003 BMW 530i, 2002 BMW 530i, and 2001 BMW 530i. However, it is still accessible from the selected car via links, so may be relevant.
Screw cap (1) onto special tool 17 0 007 and connect to vacuum hose of vacuum pump.
Feed vacuum pump with battery positive voltage.
Slowly apply partial vacuum to cap.
Compare opening pressure of vacuum valve.
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