Q: Soft brake pedal after replacing rear brakes and master cylinder 2003 Audi A4

asked by on June 10, 2017

Changed rear brakes in vehicle, afterwards had a soft pedal. Suspected it was a bad master cylinder, replaced master cylinder. After replacing and properly bleeding master cylinder, problem still persists. Soft pedal. Removed calipers and there is no pressure to the rear brakes at all. Very lost on this one. Any advice would help!

My car has 102000 miles.
My car has an automatic transmission.

Hello. If you have no pressure to the rear calipers at all and if the master cylinder is new then you may have forces some debris into the ABS unit when you compressed the pistons in the rear calipers. In some cases the system can be pressure bled to fix it but it may need a new ABS unit.

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