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Q: Brake pedal goes 3/4 way to floor

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When I'm stopping my car, the brake pedal goes ¾ way to the floor. I'm exhausted from pumping the brake pedal! I have replaced/repaired the following: new master cylinder, brake booster, new pads, new rotors and I adjusted the rear brakes along with bleeding the brakes. Even after all this, the brake pedal still goes ¾ way to the floorboard. I also removed the drums to look for a fluid leak and I didn't find any fluid. When I'm driving 20 mph and slam on the brakes, it will stop; however, at 45 mph it takes 3 extra seconds more to stop than it normally did before this problem. The brake pedal does not feel loose or spongy; it just goes down too far. If something were to run in front of my car while going around 55 mph, I wouldn't be able to stop in time because the car would go 4 feet beyond what it should. I've been working on cars for a decade and I just can't figure out what is causing this. Can you give your assessment of this and the solution for this problem?

A: Hello there. This is a more unusual problem...

Hello there. This is a more unusual problem, especially given the amount of parts you have replaced. In most cases, the pedal travel is due to either the master cylinder or the brake booster, sometimes both.

Given that these have been replaced, there may be other causes. The most likely fault that comes to mind would be that there may be air in the brake fluid system or one of the brake calipers could be stuck requiring extra travel to engage.

This can occur over time and brake fluid attracts moisture or from replacing the brake components. Some vehicles may be difficult to remove all of the air from when bleeding and require the vehicle to be bleed different ways. If the brake system was vacuum bled then it may need a mechanical bleeding to resolve the issue. If you would like to have this done, a certified mechanic can diagnose your brake pedal issue and determine what should be done next.

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