Hi,
I have a 2002 Honda Accord V6. Very recently the following started happening: If I put the brakes on solid (fairly quickly), the car brakes and the pedal stops moving down. However, if I let off some pressure on the pedal (not completely, just a little), then the pedal will start sinking again. With more pressure it stops, but again will travel towards the floor if I let up a little. It would ultimately go almost to the floor. If I pump the brakes, the pedal catches/stops higher and higher, braking the car. Now for the change after I got it 'fixed':
The garage changed the master cyllinder and bled the brakes. They also changed all the pads and rotors since one pad on each axle was getting too thin and the rotors could not be turned. Now, the car brakes but the brakes feel soft, and the pedal goes almost to the floor. A big difference is that the brakes NO LONGER respond to pumping. That is, pumping no longer makes the brakes brake at a higher position. The pedal always goes back down to the same spot. So changing the master cyllinder/bleeding brakes took away my ability to get better braking by pumping.
Thoughts? Specifically, I'm concerned the master cyllinder was not the problem originally. I've only driven the car home from the garage today but felt like maybe the brake pedal may still travel further down some if I reduce my pressure on it. What else can cause this problem? I would have thought that the power booster is working if pumping gave me strong braking previously. I could have gotten a defective master cyllinder but why the change to where pumping doesn't work if I just replaced one bad master cyllinder with another?

Oh, importantly, there was no brake fluid loss with the original issue or so far now (no reduction in reservoir).
Thanks!

 

I wonder if they got all of the air out of the lines or the master during the replacement. You can try bleeding the brake system.

For a hydraulic issue, it almost has to be the master cylinder or maybe a rubber hose that is bulging?

 

Thanks for the reply, PAhonda. It does seem the Master Cyllnder replacement has stopped the brakes from going to the floor. Also, driving it a few days now the brake doesn't seem to go as far down to the floor. Can air in the upper part of the line or Master Cyllinder or ABS come up to the Master Cyllinder and escape over time? In any case, it still does not seem to help to pump but the brakes are better than when I wrote this post and all I did was drive it for a few days.

 

I recall an ericthecarguy youtube video where he claimed taking your car and doing some hard braking (45mph to 10 mph) on a road without traffic a few times would seat the pads and give a better brake pedal feel. This might also allow the mater cylinder seals to seat as well. Maybe this is what is happening on your car right now.