Q: Brake booster heat questions again...

asked by on

So I'm having issues with the brakes having a slight drag with heat. Master is a new German replacement. (Second time it's replaced to verify good) booster is new aftermarket. VW added a brake booster heat shield in years after mine and I'm wondering what a brake booster would do if it's getting hot from exhaust and turbo heat. It's not extremely close but my injectors are very worn so I suspect my egt is higher than normal due to overfueling. Pulling the pedal up (unnoticeable amount) causes them to release smooth as glass but it happens again soon. Any ideas would be great. It's all 4 brakes dragging, new soft lines all around, new calipers too. My car has 255000 miles.

My last answer from someone said that it could be caliper debris. When the car is cool the brakes work fine. Cold outside, fine. Brakes drag evenly on all 4 wheels, lifting the pedal releases it. Is there something in a booster that heat can make it slightly engage? Still cant find this out.

My car has 253000 miles.
My car has a manual transmission.

Hi and thanks for your question. The brake booster is vacuum operated and only aids in the stopping force to the driver’s foot pedal. If vacuum pressure drops, then the foot pedal feels very firm, just like stepping on the brakes with the engine off. If you are having to pick up on the pedal and the brakes are fully disengaging, then check the return spring on the brake pedal. It may need to be replaced because it is causing the brake pedal to slightly apply itself with the engine running. The other thing is the brake master cylinder could be defective and causing the pressures to be applied at all times. I recommend checking the return spring on the brake pedal and replacing it if necessary. If you need further assistance, a technician from Your Mechanic can come to your location to inspect and repair your brake issues.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Brake booster heat questions again...

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: The eml light turned on and then the car decelerated. Just wanted to know what it means and if I require a mechanic

EML refers to the electronic throttle control system. It's a system integrated into the engine and body controllers to select the proper the throttle position for whatever the driver is demanding. There are several sensors and actuators in play and...

Q: Car air conditioning blows cool but not cold air

Air conditioning is a complex and delicate system. The only way to properly diagnose a system is with a lot of specialized equipment. There are too many variables to guess. A short list for a under-performing system are: a weak...

Q: back right wheel blocked

Hello. If the wheel will not move, then the brake shoes are stuck to the drum. If the vehicle has not moved in some time and if the parking brake was not being used, then the shoes typically corrode to...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...