When I press the brakes in a car, there is a sort of hissing, almost compressed air sound coming from the brake pedal. What causes that? - Quora
Can the brake booster cause the brake pedal to go to the floor? Also when the engine is turned on, a hissing noise comes from the booster especially when the brake pedal
Does the power brake booster make a hissing or bearing noise until appling brakes which changes the pitch of noise?
Hissing Noise From Car But Stops When Braking - What Could Be Wrong?