Clutch Sticks to Floor

[RGoessl]

So I pulled off the freeway and into city traffic yesterday when I noticed the clutch started to feel a little... sticky when I was pressing it in. The resistance of the pedal was not consistent throughout the stroke. Then the situation quickly got worse, the clutch pedal stuck to the floor. After lifting my foot, it would take a few seconds before popping out and jerking the car into gear. Kept getting worse to the point where it was stuck for over a minute before popping out so I pulled over. Tried giving the pedal a few kicks to see if I could get something unstuck (hadn't driven the car for a few months, figured maybe something seized up). No luck, I could manually actuate the pedal back and forth but the clutch was stuck open and would not engage.

So I got a tow back to my place, let the car sit for a few hours. When I decided to roll it into the garage to take a look, I figured I'd play around with the pedal again. Wouldn't you know it, my clutch is working perfectly fine again and I drove it straight into the garage.

Is my clutch getting kickbacks from the tow company, or do you guys have any insight here? I'm assuming it's something heat related. I don't know much about clutch hydraulics, anything I should be looking for there?

Any help is appreciated.

It's a 2004 Aveo, 5-spd Manual, ~145000kms, stock drive train

[Daox]

It is probably your clutch master or slave cylinder. One is leaking and not allowing the clutch to actuate properly.

[RGoessl]

Replaced slave cylinder on clutch (really easy job, easily accessible from front of engine), bled the system same way you bleed brakes. Seems to be working fine so far.

Return spring on old cylinder didn't seem to be working. I think the piston was also sticking to the cylinder wall based on the behaviour.

[aveo$3d@n08]

I think we have the same issue. Thanks for this post. I have never bled a clutch or break. I am new to fixing cars. Thanks once again.

[OG-Lou]

My clutch pedal stayed on the floor when the car was new and the temperature was -20F. After putting 5K miles on the car I never had trouble again.

[AKSoapy29]

I believe I have the same issue. It only happens when it gets really hot and humid out after running for a little bit. I took this video from a parking lot. It is actually the second video I took. With the engine off, the pedal never returned, so I had to turn the engine on and start the new video. https://youtu.be/Y8clwozw6DI

So this is likely the slave cylinder?

[OG-Lou]

My clutch pedal stayed near the floor when the car was new and the temperature was below -20F. It quit doing that as much after the car had had 20K on it.

Just the other day (temp around +70) it did it again with 57K miles on the car.

Back in my being a mechanic days, vehicles had what I called "over center springs" on the clutch pedal. This over center spring helped lesson the effort to push the clutch pedal down once the clutch pedal was about half way down. It overcame some of the spring pressure of the clutch pressure plate and made holding the clutch pedal down for extended periods of time easier.

I suspect if a person took out the rod of the slave cylinder that connects to the clutch release arm, a person could manipulate the clutch foot pedal and determine if the Aveo had an "over center spring" that assisted in overcoming the spring pressure of the clutch pressure plate, which is sometimes called the clutch cover.

Or if you want to change the clutch fluid as a maintenance procedure, drain the fluid and play with the clutch pedal travel.

I know some 1960 vehicles with coil spring pressure plates had a strong "over center" spring on the clutch pedal arm and the clutch pedal once depressed with the clutch linkage disengaged, it took some effort to get the clutch pedal off of the floor.

[RGoessl]

I believe I have the same issue. It only happens when it gets really hot and humid out after running for a little bit. I took this video from a parking lot. It is actually the second video I took. With the engine off, the pedal never returned, so I had to turn the engine on and start the new video. https://youtu.be/Y8clwozw6DI

So this is likely the slave cylinder?

Mine was doing the exact same thing. Changed the slave cylinder and it's been fine for 40k.

[fancypants]

My clutch pedal stayed on the floor when the car was new and the temperature was -20F. After putting 5K miles on the car I never had trouble again.North Shore house washing

I see, thanks for sharing.