[tyytyy22]

When i'm driving, sometimes there will be brake pressure and somtimes
there won't. If i apply pressure for a few seconds, the pedal loses
presure and goes to the floor. I have to pump the brakes to get the car
to stop. I tried bleeding the brakes and got through the back to wheels
fine, but when i tried to bleed the front right brake, air bubbles kept
coming out. After refilling the resivoir for the 3rd time (it never got
completly empty), i got the idea that it might be somethign more
complicated. I was able to bleed the front left with no problems but
the same thing kept happening when i tried to drive it. I checked all
the lines and can't find any leaks, but i have an oil leak so i might
be missing something thinking its just oil and not brake fluid. There
is some black fluid underneath where the brake booster connects to the
master cylinder but i don't konw if its coming out of there or is oil .
I can also hear some air come out of the brake booster inside the car
but i dont' know if that is normal. I don't know too much about brakes
and i don't want to take apart the whole system before i know what to
look for. Any ideas?

[Kuasimodem]

It sounds to me like you master cylinder may be going bad, especially with the fluid at the mating surface of the booster and MC.

The brake pedal going to the floor after holding it for a few seconds is also an indicator that says bad seals in the master cylinder.

[AZ Jeff]

Originally Posted by Kuasimodem

It sounds to me like you master cylinder may be going bad, especially with the fluid at the mating surface of the booster and MC.

The brake pedal going to the floor after holding it for a few seconds is also an indicator that says bad seals in the master cylinder.

ABSOLUTELY. Your MC is bad, and needs replacement.