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Q: Master cylinder issues with vehicle. Hard to stop.

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Brake pedal occasionally goes all the way to the floor and I have to pump it to stop the car. I was told it could be a master cylinder booster or the master cylinder itself.

The booster won’t make your pedal go to the floor. If you bled all the brakes, and there are no leaks, then it’s most likely the master cylinder. You can take them apart and clean them, but if the seals are too bad then you should just replace then bleed the brakes again. A mechanic from YourMechanic can do the above as well as perform a brake safety inspection if you would like.

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