Low Pressure Test
WARNING: This page does not describe the selected car, but rather 43 other vehicles, including the 2006 BMW M3, 2006 BMW 330Ci, 2006 BMW 325Ci, 2005 BMW M3, and 2005 BMW 330xi. However, it is still accessible from the selected car via links, so may be relevant.
- Remove left microfilter for interior ventilation. See 64 31 010 REPLACING MICROFILTER FOR INTERIOR VENTILATION
- Pull hose off connection. Install Vacuum Tester (34 3 100) between connection and vacuum hose on non-return valve. See Fig 1.
- Start engine and check buildup of partial vacuum. Stop engine.
- Press brake pedal to set a partial vacuum of no more than 11.6 psi (.8 bar) and wait for value to stabilize.
- When brake pedal is not pressed, partial vacuum is allowed to drop by maximum.8 psi (.06 bar) over a test period of one minute. If specified values are not reached:
- Check line connections for vacuum seal.
- Replace vacuum non-return valve.
- Check seal between brake booster and brake master cylinder (sealing ring) for perfect condition and correct seating.
- If specified values are not achieved when test is repeated, replace brake booster. See BRAKE BOOSTER under REMOVAL & INSTALLATION.