A sign of a malfunction in the operation of the vacuum brake booster is an increase in pedal effort during braking compared to normal.
To do the job, you need a rubber pear.
Execution sequence
1. We prepare the car for operations (see "Vehicle preparation for maintenance and repair").
2. With the engine off, press the brake pedal 4-6 times.
3. While holding the pedal, we start the engine. With a working vacuum booster, the pedal should move slightly forward.
Otherwise, check the tightness of the connections:
- check valve with a vacuum booster and vacuum supply hose;
- vacuum supply hose with inlet pipeline.
4. Check the operation of the check valve; if it malfunctions, a vacuum is not created in the vacuum cavity of the amplifier. Having disconnected the hose from the check valve, we take it out of the rubber seal of the amplifier. We introduce a rubber pear into the hole of the fitting of a larger diameter and squeeze it. If the bulb remains compressed, the valve is good.
Otherwise, replace the check valve.