Also, what does a vacuum check valve do? A vacuum check valve will only allow air to move in one direction. There is a check valve on the brake booster line coming off of the intake manifold that does not allow the vacuum that the booster needs to bleed off when under a WOT condition (no vacuum). It may be used for different things elsewhere.
Consequently, how do you test a vacuum check valve?
Vacuum Inlet Check Valve Test: To test the vacuum check valve, disconnect the vacuum supply hose from the intake manifold or vacuum pump, and blow into the hose. If air passes through the valve into the booster, the check valve is defective and should be replaced.
How do you change a vacuum booster on a check valve?
Part 1 of 1: Replacing the vacuum brake booster check valve
Materials Needed. Step 1: Open the hood. Step 2: Locate the brake booster check valve. Step 3: Remove a gear type clamp. Step 4: Remove a spring type clamp. Step 5: Remove the brake booster vacuum hose. Step 6: Remove the vacuum brake booster check valve.