How to tell if brake booster on a 96 Chevrolet z71
Is bad? Most of them will leak vacuum when you step on the brakes with the engine running, you will hear this on the inside for the car. Some if the diaphragm is rotted inside the booster just won't work and your engine RPM' will be slightly higher due to and unmetered vacuum leak. Finally the check valve can go bad that where the vacuum line connects to the booster, most obvious when you turn off the engine with your foot on the brake the pedal will go hard almost instantly. HTH
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