Symptoms of a Bad or Failing Brake Booster Vacuum Sensor

Brake booster vacuum sensors are an electronic component found on many vehicles equipped with vacuum pumps for their brake boosters. They are usually installed in the brake booster and work to monitor the amount of vacuum present inside of the booster. They monitor the vacuum level to ensure that there is always enough vacuum present for the power brakes to operate correctly, and will set off a brake or service booster light when they detect that the vacuum has fallen below acceptable levels.

When they do fail, the computer loses an important signal as the vacuum measured by the brake booster vacuum sensor is what allows the power assisted brakes to work. Usually, a vehicle with a failed brake booster vacuum sensor will produce a few symptoms that can notify the driver of a potential problem that should be serviced.

Stiff brake pedal

One of most commonly associated symptoms of a problem with the brake booster vacuum sensor is a stiff brake pedal. A stiff brake pedal is usually caused by there not being enough vacuum present due to a problem with the brake booster vacuum pump. However, if the pedal become stiff and the brake or service booster light is not illuminated, then that means the sensor is not picking up on the low vacuum levels and may be having a problem.

Illuminated Check Engine Light

Another symptom of a problem with the brake booster vacuum sensor is an illuminated Check Engine Light. If the computer detects a problem with the brake booster vacuum sensor signal or circuit, it will set off the Check Engine Light to alert the driver that a problem has occurred. A Check Engine Light can also be set off by a variety of other problems, so it is important to have the computer scanned for trouble codes before proceeding with any repairs.

The brake booster sensor is an important piece of the braking system for vehicles equipped with brake booster pumps. They monitor an important signal for the vacuum that allows the entire power brake system to work. For this reason, if you suspect that your brake booster may be having a problem, or your Check Engine Light has come on, have the vehicle’s brake system diagnosed by a professional technician, such as one from YourMechanic. They will be able to determine if your car needs a brake booster vacuum sensor replaced, or if another repair is needed to restore functionality to your brake system.


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Johnny

33 years of experience
264 reviews
Johnny
33 years of experience
Toyota RAV4 L4-2.4L - Brake System Inspection - Sacramento, California
Johnny arrived early which was great, he performed the inspection in less than half an hour, and gave us a complete quote for all items needing attention, including the brakes as our main concern. Johnny is fast and efficient so I scheduled the work done by him.
Ford Escape - Brake System Inspection - Sacramento, California
The convenience is worth the cost. I was also tired of the dealership not really caring about my old car. Last couple of times I had to wait well over an hour to get my car after the dealership said "It's ready!". They also wouldn't fix the things I asked saying they didn't have time and I need to come back.

Jay

37 years of experience
947 reviews
Jay
37 years of experience
Chevrolet C10 Pickup V8-5.4L - Brake System Inspection - Moreno Valley, California
Knowledgeable, Professional, Friendly, and PATIENT! Sickeningly HONEST, as I tried to ply him with cash, alcohol, outside work, and wild dancing girls - although I wouldn't have "ratted him out" if he HAD accepted. A guy like this needs a "bigger cut" than what you are paying him ... because loyalty like his is hard to find these days! THANKS!
Volkswagen Jetta - Brake System Inspection - Moreno Valley, California
As usual, Mr. Jay provides efficient and professional quality of work. I would highly recommend him to any customer searching for a good mechanic.

Christopher

10 years of experience
114 reviews
Christopher
10 years of experience
Ford Explorer V6-3.5L - Brake System Inspection - Katy, Texas
Christopher was very knowledgeable and was able to address our concerns. We would trust him with future service needs.

Jesse

16 years of experience
61 reviews
Jesse
16 years of experience
Nissan Frontier V6-3.3L - Brake System Inspection - Flagler Beach, Florida
Jesse took the time to explain everything that was going to be done and why and then proceeded to repair my truck not only professionally but quickly. As a disabled Veteran and no longer able to perform work that was needed to be done it is nice to know a mechanic such as Jesse will take the time to explain all the various issues and what needs to be done before a blanket you need everything. After Jesse went thru everything I felt comfortable that all work was required and needed. 8 can safely say I will use yourmechanoc .com again and hope I can request Jess

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