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.

In addition to that, automotive vacuum brake boosters can malfunction owing to the disconnected or incorrect vacuum hose, failed check valve, low vacuum pressure from the vehicle's engine ...

When one of those hoses, fittings ... A good place is through the large-diameter vacuum line to the brake booster.

Slang words aside, like a spider hose, some stuff just makes sense ... One would be an increase in noise as all vacuum brake boosters make a light pump-like noise. But if it gets louder than ...