Soft brake pedal on 1994 Mazda Navajo

Replaced Master cylinder (2 times), Vaccuum booster, calipers, rotors, pads, wheel cylinders, drums and shoes. Had HCU bled at ford dealership. pressure bled system 2 times, still pedal sinks to floor. If pumped will build pressure. Soft application will sink to floor. HELP

by in Lincoln, CA on February 14, 2011
1 answer 2 comments
ANSWER by on February 14, 2011
Sounds like you surely replaced just about everything. The only possible causes of issue at this point are: 1) air in the lines 2) faulty master cylinder. Obviously, the master cylinder being replaced twice makes this part less likely to be bad. However, it is possible. Try to bleed the system thoroughly again - get some assistance if needed.
COMMENT by on February 15, 2011
Thank you for reply. Could bad HCU be an issue? 4 wheel abs system. The most current feedback I received from Ford is possible valve stuck in HCU. Will try to pressure bleed brakes with new machine, used cheap vaccuum set up last 2 times. Once again, thank you for the reply.....
COMMENT by on February 15, 2011
Very much doubt an HCU. Usually, a failed HCU with a stuck valve will cause a pull, but not a soft pedal.