Most brake boosters run on a vacuum produced by the engine. The cause of booster failure can be as simple as a loose vacuum hose or a ruptured diaphragm that requires component replacement.

This can help identify a leaky component like a brake booster or distributor ... Tests If A Visual Check Reveals Nothing If ...

The check engine light on your dash ... pump the brakes several times. (Brake booster design allows the mechanism to hold ...