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Q: Brakes spongy after booster and master cylinder replacement

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I had to replace my brake booster and master cylinder. After I got it all back together my brake lights won't turn off unless I disconnect the battery and I can not get the brakes to bleed I am doing it the manual way since I don't have a vacuum bleeder

My car has 169000 miles.
My car has an automatic transmission.

Hello. You need to double check the installation since you may have put the brake booster rod on the brake pedal wrong causing binding of the brake switch and causing the system to not bleed correctly. Also make sure the brake booster to the brake master cylinder push pin is adjusted with the proper clearance. It may be holding the master cylinder partly pressed. If you would like to have expert assistance on this, a certified professional from YourMechanic can come to your car’s location to diagnose the brake symptoms and address the issues properly.

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