Hi, looking for help regarding my mk6 fiesta. Noticed last week it was a bit stiff going into gears and took it a run the other day, eventually had to pull over as it wouldn't select any gears and there was no clutch pedal pressure at all. Had to call the RAC. They gave it a quick check over, fluid levels OK and bled it a bit but no result. They towed it home for me and dropped it off. The car has sat for 2 days, went out today to try move it off street and it it seems to be working fine, clutch pedal normal and going into gears easily. Iam going to take it to a garage after the holidays, was just looking for any suggestions, ps I checked the plastic push rod is connected to pedal although there does seem to be no nut or pin on push rod. Any help appreciated! 

1 hour ago, PaulLecky said:

fluid levels OK and bled it a bit but no result. They towed it home for me and dropped it off. The car has sat for 2 days, went out today to try move it off street and it it seems to be working fine, clutch pedal normal and going into gears easily.

That is a strange one, a self repairing clutch!

Most of the faults I can think of at the slave cylinder end would either lose fluid (leaks), or be permanent. I can't think of anything there that stacks up with the pedal going down to the floor easily one day, then working a bit later.

At the master cylinder end, there are more possibilities. There could be an intermittent or temperature dependant leak back to the reservoir, so pressure would be lost, but no fluid loss. Try holding the clutch down for some time, and see if the pressure drops, or the clutch slowly engages.

my sister has 2004 fiesta which will have same clutch hydraulics as yours. 

some months ago the clutch went like yours (no clutch fluid pressure) and she abandoned car some miles from home. I went there a few days later to tow home. First thing I did before moving the car  was check the clutch cylinder push rod. it was fine (someone had in past drilled hole and put a split pin through it). after pushing the clutch pedal down about three times the clutch was suddenly perfect again. The car was  driven home some miles, but when almost home it totally lost fluid pressure again. A few pumps of pedal some pressure came back, enough to drive it rest of way home. 

Tried the next day and clutch was fine again.  there was no sign of fluid leaks anywhere and fluid level had not gone down. I knew where the fluid level was as I had replaced discs/pads a few weeks earlier.

I couldn't leave my sister with a car that might do it again particularly with two young children.

I could only think that the master cylinder was faulty inside. So  I bought a new one from euro car parts. About £18 and fitted it.  Bit fiddly to fit due to access but did not require any advanced skills. 

Car OK for a few months but a week ago it did same thing again. Intermittent and does seem to be 'self repairing' . Still no signs of any leaks and fluid not gone down.

I thought may some dirt in fluid affecting master cylinder seal. So I have bled it again putting a load of new fluid through it.  But I have not bled new fluid through all of the brakes and as the brakes share the same reservoir it mixes with cruddy brake fluid.

Car perfect at the moment but I am not confident it will be fine forever as did not really find what was wrong.

Regarding bleeding - bleed screw is quite hard to access (at least of her 1.4tdci it is). It is plastic and to open it turn anti clockwise 1/4-1/2 turn. you might be able to do with fingers, might need spanner to move first time.

Bleeding it in the traditional way I found it to be hopeless, could not seem to get pressure when bleed screw done up. the way I bled it was to fill reservior, open bleed screw, put my mouth over the top of reservoir and blow hard, make sure fluid level goes down to prove you blew some through, do bleed screw up. this seemed fine. 

 

additionally, after i replaced master cylinder I thought I would inspect inside of the old one. as far as I can tell you can not take the piston out without breaking the cylinder as the part where the pushrod goes seems to have a collar glued on. so I broke the thing apart. I could not see anything obviously wrong. I was hoping to see something (eg decaying/split seal) wrong so that I knew I had found and fixed a definite fault. but it all looked fine.