HELP! My clutch pedal is dead

[2turboimports]

Where to start....ok, My clutch is dead against the floor of the car, can't get any pressure out of it. When i pop it up, it'll fly right back to the floor when my foot touches it.

The fluid resovoire is full, there are no visible leaks or cracks on the slave cylinder. The T.O.B. is firm in place with a tiny bit of play, nothing out of the ordinary I assume.

Prior to the clutch pedal flying to the floor I had been noticing for about 3 weeks now that when I'm at idle with the car in neutral and my foot off of the clutch there is this knocking sound. I thought it was the engine or exhaust (both are quite a bit ragged out) then i noticed when I push in the clutch the noise slows down and stops. Let off the clutch, it's back. At first I thought it may be the TOB but the noise isn't flutterly and high pitched,also the noise doesn't stop when the clutch is have engaged. In 1st and 2nd especially the transmission has been noisier than usual. I pulled the car into my parking lot, go to back in, put in reverse, had to stall it, then put it in neutral.

Any ideas. I'm guessing it has more than likely something to do with the hydraulics, but with the resovoire full, no problems previously with the clutch pedal feel, and no visible leaks, i'm not so sure. Thanks in advance for any help.

[curtis73]

Without knowing the make model and year its hard to tell, so I'll guess.

It sounds like clutch master cylinder is bad. It doesn't have to leak to be bad. The master cylinder is a piston inside a bore with an O-ring seal. If that seal goes bad, the fluid squeezes past it instead of being pushed ahead to the clutch.

[2turboimports]

ooh yes, that infamous make/model detail...lol

sorry, i copy and pasted my question from another site. It's an 01 Subaru Impreza RS. I was always under the impression for the master cylinder to go bad that there would have to be a leak somewhere. But I'm thinking that it's the o-ring inside the chamber. I'll find out today. Thanks man.