How to fix a sticky clutch?

Goodness, it's not supposed to do that! The problem could be mechanical or hydraulic.

Mechanical:
The pedal is binding on its shaft.
The pedal return spring is broken.
The clutch splines are sticking. (pedal should still return?)
The pressure plate has broken fingers. (pedal should still return?)
The release bearing is binding on the flange.

Hydraulic:
The clutch master cylinder has a stuck seal.
The system needs to be bled (air or bad fluid in the system).


I would think that the pedal would still return if there was air in the fluid and the system needed to be bled, but air in the system may possibly cause the master cylinder to stick, but it should prevent the clutch from operating. Curious problem. Based on your description, my bet would be that the clutch master cylinder is sticking, and that it MAY help to bleed the system. Is there any possibility that the system was previously bled or topped up with the wrong type fluid?

 

Remove your floor mats (they are notorious for catching clutch pedals and accelerator pedals). Add brake fluid DOT 4 into your reservoir. Have your system bled.

Work your clutch vigorously in a parking lot so that you can replicate your problem on demand.

 

Do the floor mats ride up that high to get caught on the clutch pedal?? Its mainly the accelerator pedal that gets stuck because of the mat.
Its very hard to diagnose a problem without looking at the car as we all know....but id firstly check around the brake pedal area,to see if any obstructions,or bent shaft,binding or the return spring has broken or come off. Then i would try to bleed the system and see if any air comes out. If the wrong brake fluid was used(unlikely)the master cylinder seals can swell up and cause you grief. Other than that,happy hunting

 

Try a bleed 1st,but now that you mention it.........You could have a sticking throwout bearing/slave body or the seal in the clutch mastercylinder is by-passing(worn/leaking). But do a bleed/flush 1st,then see what happens from there.