BMW 5 series E39

Since 1996-2001 of release

Repair and car operation

Check of the vacuum amplifier of a brake

If for achievement of necessary brake effort it is necessary to make considerable effort a brake pedal, it is necessary to check up the vacuum amplifier of a brake.

PERFORMANCE ORDER

1. Press a brake pedal at the idle engine not less than 10 times. Then, without releasing a pedal, start the engine. Thus pressure of a pedal of a brake under effort of a foot should weaken. In this case the vacuum amplifier is serviceable.
2. Otherwise disconnect a vacuum hose from the amplifier and start the engine. Put a finger to the end of a vacuum hose and check up, whether there is a vacuum.
3. If the vacuum is not present: Check up tightness of a vacuum hose and presence of damages. If necessary replace. Tighten all collars.
4. The diesel engine: Disconnect a vacuum hose from the vacuum pump and check up a finger vacuum presence.
5. If the vacuum is: Measure value of vacuum. If necessary replace the vacuum amplifier (work HUNDRED).

Thus necessarily replace the return valve in the vacuum pipeline, since. The diaphragm in the amplifier can be damaged owing to penetration of steams of fuel (at the petrol engine and the damaged return valve). Arrows on the return valve should specify in a direction of the inlet pipeline.