What makes a hissing noise when you press the brake pedal?
An expert that got 20 achievements. An expert that got 10 achievements. This noise is caused by a defective power brake vacuum booster, (big round thing behind the master cylinder) the diaphragm is leaking vacuum. You can’t post conmments that contain an email address.
When do you press the brake there is no sound?
My fluid was at a normal level, the sound only occurs when the car is moving. If it’s a few mph or stationary, there is no sound when pressing the brake. Any help is appreciated. Thanks The test you conducted checks to see if the brake booster is working, and not leaking with the pedal released.
Why does my vacuum make noise when I push the pedal?
The vacuum boost section has a leak and will not seal on the push rod when the pedal is depressed. The leak is not sufficient to prevent booster operation, so there will be no other obvious indication. You can disconnect the vacuum hose at the booster (and plug the end) to see if the noise goes away.
Why does my brake pedal make a hissing noise?
If you hear a hissing noise from under the dashboard that changes when you press or release the brake pedal area, it most likely is a brake booster that is failing. Brakes sound like air is coming out.
My fluid was at a normal level, the sound only occurs when the car is moving. If it’s a few mph or stationary, there is no sound when pressing the brake. Any help is appreciated. Thanks The test you conducted checks to see if the brake booster is working, and not leaking with the pedal released.
The vacuum boost section has a leak and will not seal on the push rod when the pedal is depressed. The leak is not sufficient to prevent booster operation, so there will be no other obvious indication. You can disconnect the vacuum hose at the booster (and plug the end) to see if the noise goes away.
What to do when your gas pedal makes a hissing noise?
In some cases, you may notice that the noise goes away when you press the brake pedal or gas pedal. Replacing the brake boosterwill fix this problem. Replacing the brake booster requires some DIY skills so if you don’t plan on fixing the hissing noise yourself take your car to a mechanic.