The clutch pedal on my Honda civic 2001 get down and I cannot change the speeds. Following several YouTube videos, I replaced the master and slave hydraulics. When the slave seems to be bad the master looks good, but I replaced both and spend a lot of time purging the circuit. But despite it the pedal is still down. Is there other cause for it?
I’ve had to replace/bleed the clutch master cylinder on my Corolla a few times over the years, symptom is similar to yours, hard to shift gears even if clutch pedal pressed. Replacing CMC is all I ever needed to do to fix symptom. Slave seems pretty robust. If I had the same symptom on my Corolla and replacing CMC didn’t fix it, I’d look at what happens to the linkage from the slave to the bell-housing when pressing on clutch pedal. Is yours also configured like that? On newer cars slave is often inside the bell housing, so can’t easily see that part.
Make sure that when you press clutch pedal it causes the CMC plunger to plunge fully. Could happen if clutch pedal linkages under the dash were faulty.
Bleeding clutch circuit very simple job on Corolla. Is the bleeding valve on your car near the slave? If so, and you open it, does fluid come out immediately when helper presses slightly on the clutch pedal?
If you’d like a wild guess, seems pretty likely your problem is with the clutch mechanism inside the bell housing, rather than the hydraulics. Some manual transmissions are configured with access cover so you can peek inside to see what’s happening. Never had to do that w/my Corolla’s M5 transmission though, so don’t know if it has such a cover. (Keep your old CMC and old slave, may still be good.)
A broken pressure plate spring will do that. So will a broken clutch fork. You should have been able to feel that when you replaced the slave cylinder.