Examination
1. Press the brake pedal several times with the engine off to create equal 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. If the vacuum booster is working properly, the brake pedal should move forward after starting the engine. If the pedal does not move forward, check the fastening of the hose tip, the condition of the fastening of the flange of the tip in the booster, the condition of the hose and the nipple.
4. On vehicles with diesel engines, also check the functionality of the vacuum pump.
Removal
1. Remove the brake master cylinder.
2. Loosen the clamp and disconnect the vacuum hose from the brake booster one-way valve. Inside the vehicle, remove the fuse box cover.
3. Disconnect the electrical connector from the key socket, unscrew the mounting screws and remove the lower instrument panel trim. Remove the mounting bracket and remove the pin with a head and a hole for a cotter pin that secures the brake pedal pushrod to the brake booster.
4. Unscrew the nuts securing the vacuum booster to the engine compartment bulkhead and remove it.
Installation
1. Before installing the vacuum booster, measure the distance from the end of the vacuum booster pushrod to the mating surface of the brake master cylinder, which should be 22.3±0.1 mm.
2. Make sure the gasket is properly seated on the back of the booster, then install the booster into the engine compartment.
3. Check that the pushrod is properly aligned with the brake pedal, then screw on the brake booster mounting nuts and tighten them to the specified torque.
4. Align the pedal with the pushrod, insert the pin with the head and hole for the cotter pin and secure with the mounting brackets. Install the lower instrument panel trim.
5. Connect the vacuum hose to the one-way valve and secure with a clamp.
6. Install the master cylinder and bleed the brake system.