Removing
1. The control valve is built into the brake booster servo vacuum hose.
2. Carefully release the vacuum hose from the servo unit, remove the rubber grommet.
3. Moving back along a hose, release it from all intermediate clamps, then release a collar and disconnect a hose from the inlet pipeline/vacuum pump. Remove the hose assembly from the engine compartment. do not attempt to remove the valve from the hose.
Examination
1. Carefully inspect the valve with hose for signs of mechanical damage. Replace if necessary. Checking the correct functioning of the valve can be done by blowing it in both directions. Air should pass through the assembly in only one direction - from the side of the vacuum booster. Otherwise, the valve must be replaced.
2. Check the rubber bushing of the valve for damage and signs of material ageing. Replace if necessary.
Installation
1. Installation is carried out in the reverse order. Track correctness of laying of a hose and reliability of a tightening of a fixing collar.
2. Fit the grommet firmly into the servo assembly and thread the vacuum hose end fitting into it (try not to damage the bushing).
3. Finally, start the engine and check the relevant components for signs of air leaks.