95 VR6 Passat clutch pedal went to the floor and won't come back up. Installed new slave, bleed but still won't build preasure. The pedal and plunger under the dash seem OK. How can I tell if it's the master or the clutch/preasure plate assy? HELP

Did the system lose hydraulic fluid to begin with? I assume that is why you replaced the slave. Hydraulic clutches can be very difficult to bleed. Have someone push the pedal and watch to see if the slave moves fully. If not keep trying to bleed. If it moves fully the problem may be in the clutch. If the master is bad it would probably leak where push rod goes in, but could be bypassing internally.

this happen to me when i had my 95 golf. the clutch pedal went to the floor and won't return at all while i'm driving. after towing the car home and pull the transmission out. i found out that the rod broke inside the transmission and thats why the pedal won't return. but mine is a cable type system. hope this help.

Thanks, Boshmann. What you suggest makes sence but how can I check if the slave plunger is fully operating while it's installed in the car? Should I unbolt it from the car (leaving the hydraulic line hooked up)? Didn't see any leaks. Thanks

If you can't see it you might have to remove it the way you describe, but be very careful not to push the piston out of the cylinder by pumping too many times in succession. One problem with this is that it may move even if air is still in the system, because it will have no resistance from the clutch. Do you have access to a pressure or vacuum bleeder?