Need help with a brakes problem

[kainvamp]

Well i was getting ready to roll out the driveway to work thismorning when i suddenly had no brakes. I figure it is the master cylinder, since the pedal goes straight to the floor with no pressure. My question is how would I know if it is the master cylinder or the brake booster that f'd up. The resevoir was still full so its not a leak or anything. A quick response would be greatly appreciated.

[kainvamp]

well i didnt really understand how the brake booster worked until i just read up on it, so im assuming its just the brake master cylinder now

[Hijacker]

the internal seals on the MC probably went bad so instead of the fluid staying in the line or even leaking anywhere, it just goes back into the resevoir. Master Cylinders aren't too terribly expensive.

[blackmagic]

Im with him^

[Vegascorbin]

When the brake booster goes bad it will be hard to press on the pedal. Teh same as if the engien is off. usualy when they go bad sudenly you hear it. It will "POP" just like a balloon. And your pedal will get very hard to push all of a sudden. (ask me how I know this )

[nismoracingsx]

before you throw a new master cylinder in, check for any external leaks throughout your system. Also, you can pump your brake pedal and have someone watch for bubbling in the resavoir (alot of bubbles normally means bad seals).

GL