So I'm stuck.. 2005 RX8 1.3L Renesis Automatic

Bought new brake pads, & new rotors, new master cylinder

The car still creates a problem while driving and while braking. What happens:

1) When pressing the brake, it doesn't apply enough pressure on the calipers and the rotor slips causing the car to vibrate, having trouble stopping.

2) When releasing the brake pedal, the calipers don't open back up all the way and they scrape the rotors while driving causing a "whirling" noise.

My guess was master cylinder issue. I highly doubt all 4 calipers failed all of a sudden. We've bled the brakes 3+ times and still no luck.

Any ideas?

Thank you.

 

time for new calipers or at least rebuild the calipers.

 

Check all brake parts again, and specially the master cylinder for leaks.

 

did you prime the MC before connecting all the lines back up?

Did you prefill the calipers with fluid prior to reinstalling?

in what order did you bleed the brake lines? How many times did you bleed it?

from the sounds of it, looks like there is air or water in the system. Although you could have a faulty MC, could be the secondary value it bypassing and hence why you are having the pedal go straight to the floor.

I would rebleed the system in the Z pattern, using the pump method and then do it again just to insure that there is no air in the lines. Make sure you keep the MC full of fluid while bleeding, if it drops below the min level it will allow air to enter the system.

If after you bleed the system and the pedal still doesnt feel hard at about half way down.... DO NOT DRIVE YOUR CAR!!!!! I would look into the MC or even the power booster being faulty.