Checking the brake booster (VW Golf 4)

The brake booster reduces the force on the brake pedal, making it easier to control the car. The brake booster operates by using the vacuum in the intake manifold. If the brake booster fails, the brake system will not be affected, but much more force must be applied to press the brake pedal.

Execution order

1. Press the brake pedal several times with the engine off to create the same pressure in the vacuum booster cavities, close to atmospheric.

2. At the same time, by the force applied to the pedal, determine whether the valve body is jammed.

3. Stop the brake pedal in the middle of its travel and start the engine.

4. If the vacuum booster is working properly, the brake pedal should move forward after starting the engine.

5. If the pedal does not move forward, check the fastening of the hose tip, the fastening connections of the flange of the tip in the amplifier, the condition of the hose and the fitting.

The information is posted on this website VWMANUAL.ru

6. On vehicles with diesel engines, check the functionality of the vacuum pump.