veejay

I think this needs replacing because when it's hot outside, the brake pedal goes all the way to the floor! i heard this was a sign that the master cylinder needs replacing. Could it be anything else? Anyone else experience this before? and about how much does it cost to have fixed? Thanks!

G

You should try bleeding your brakes first. Then worry about the brake master. Any brake fluid disappearing from the reservoir, leaking into the car where the brake rod is? Have you changed your brakes lately? Do you need to replace the pads and-or shoes? The brake master isn't so much a problem until you strip the compression nuts for the lines. Then, you should worry.......

92CivicSiR

You should check out your power brake booster, there is a vacuum line hooked to the tope of there with a check valve on the end of the line feeding into the brake booster. If that check valve is bad then the brakes wont function properly. I would also check your pads/rotors and bleed your brakes also.

dustin

My pedal goes to the floor now too... I am going to bleed my brakes again... heh.

VaporTrail

no no, you only need to bleed your brakes if you have replaced fluids or added. What you possibly need is a flush of the system, to remove all the old fluids - just check the color, it should be clear. Be sure to bleed afterwards. If that doesn't fix it, check the condition of the brake lines, they could be flexing. Then, if none of that fixes it, and your pads and rotors are known to be good, then assume master cylinder/ brake booster.

dustin

I just removed my ABS unit on saturday and replaced some O-rings in it because it was leaking. I had to bleed the brakes but I am not convinced that I got all of the air out because the pedal is mushy at the top, but then firms up if I press harder. As the car/air gets hotter, the pedal will eventually go all the way to the floor. If I press REALLY hard on the brakes and then let off, I hear this sucking sort of sound come from the master cylinder.

When I bled the brakes following the ABS unit reinstall, I could swear that I had all of the air out of the lines, but it still did not feel right. I have to pump the brakes to stop entirely when coming up to lights and stuff.. .sorta scary.

A few weeks ago I was just driving and the pedal went all the way to the floor at a light, but when I got home I pumped the brakes a TON and it felt fixed for a few weeks. Bleh.

Btw, I am still not convinced that my ABS unit has stopped leaking!

Dustin

Leejen

From what I hear, ABS brakes are the toughest to get properly bled.
Good luck. Both of you cats.