Q: Brakes still going to floor

asked by on December 11, 2016

I was having issues with my brakes hitting the floor. I could still stop okay, but not as fast. I took it to a shop where they replaced the master cylinder and a leaky brake line. I was still having the same problem. They ran some more tests and diagnostics and determined it to be the ABS module. My brakes function a lot better, but every once in a while they still slowly drop to the floor and I lose braking power. It seems to happen most often when I need to brake for a longer period. As far as I know, there's no air and the lines have been bled properly.

My car has 118000 miles.
My car has an automatic transmission.

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This may suggest your brake booster is failing. The brake booster is a mechanism that uses vacuum pressure to take the force being applied to the brake pedal and amplify it. If the booster is bad, then the full amount of force needed to activate the master cylinder and pressurize the brake fluid isn’t going to be there. The pedal will go all the way to the floor and the car will be harder to stop.

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