I was driving to work this morning when the clutch pedal essentially stopped working. It started sticking to the floor from 1st and although the car was still drivable the clutch had almost no resistance to it and seemed to engage almost on the floor.

I popped the hood and heard a hissing noise, and saw brake fluid running out from the center of the brake master cylinder and down into the engine bay.

This seems like an obvious problem, but how could brake fluid loss from the brake master cause a problem with the clutch? Is it actually coming from somewhere else and it just looks like the brake master? When I shut the car off for a minute, pumped the clutch, and tried to drive again, it seemed like I got some resistance back in the clutch, so maybe it's a vacuum problem?

All the clutch components are relatively new (< 2 years). Master, slave, hoses, clutch, flywheel, etc. The clutch itself was changed about 6 months ago. This is my daily driver car right now while the other one is down for an engine rebuild so any help is greatly appreciated.

 

Not at all connected or related. Loss of clutch pedal action means either the slave cylinder or clutch master cylinder needs attention. It sucks having only replaced them 2 years ago. Maybe also you have an unrelated problem with your brake booster or master cylinder. Good luck.

 

I just drove it for a minute on my lunch break and it's driving fine now. Clutch works perfectly. What could have happened? Stuck spring in the master cylinder? A little ice in the fluid on a cold morning?

 

I think you were seeing brake fluid squirting out of the clucth master and onto the brake master
if anything. You don't mention any issues with the brakes. If the brake master was leaking like
that the brake pedal would be spongy or on the floor and have to be pumped to work.

Maybe its just the connection or hose for the clutch master to slave. Did you replace it? Is it
tight? Check the simple things first.

 

Check the bleeder screw for the clutch too when you check the lines, maybe it is loose from vibration. With the bleeder so close to the brake master it could have easily sprayed. Actually, just plan to tighten all fittings this weekend then flush all fluid and bleed the system again. If you are concerned about ice that will eliminate any water issues; plus since it leaked it is probably contaminated at worst and minimally has air in the system anyway. This is a quick job on the clutch even without a mighty vac.

 

Thanks for the help.

I drove the car home yesterday and back to work today without any problems. It seems that it was a fluke and thankfully I am not stuck without a car at the moment. I'll flush the clutch fluid this weekend to be safe. I know the brake system has at least some air in it right now but the clutch should really be fine. I cleaned all the fluid up so I can see if it leaks again soon.