Removal
1. Loosen the nipple nut and disconnect the vacuum hose from the brake booster (see fig. 12.1).
Fig. 12.1. Nut of the vacuum hose fitting to the brake booster (shown by arrow)
2. Trace the hose back, then disconnect it from the intake manifold/pump fitting (depends on the model) and remove the hose and valve from the engine.
Examination
3. Check the condition of the vacuum hose and valve. If damaged, replace.
4. The valve can be checked by blowing in both directions. Air should only flow in one direction - from the booster. If the valve is faulty, replace it along with the hose.
Installation
5. Once you have ensured that the hose is routed correctly, securely connect it to the manifold/pump (depends on the model). Connect the hose to the vacuum booster and tighten the nipple nut to the required torque.
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6. When finished, start the engine and eliminate air leaks in the vacuum valve connection to the booster; check the operation of the braking system thoroughly before driving on the road.