Mate at worked asked me yesterday about a problem he has got with his Wife's car. It's a 2006 Cadillac BLS 1.9 Diesel. The problem is the clutch pedal sticks down, if you hook your foot back under it and pull it up clutch works fine. As far as I can tell without looking at the car the clutch is Hydraulic.

The garage he has taken it to wants £1k and say it is the dual mass flywheel which has failed. I can't understand how this would be. Surely regardless of the flywheel condition, the clutch fingers should be pressing the slave cylinder back and then the master cylinder in turn pushes the pedal back. As the clutch is still working, I can't see it being the clutch having collapsed so it would seem like it is a hydraulic problem, perhaps slave or master knackered. Any thoughts? The same garage heave told him the DMF alone will cost £300, look on Eurocarparts and it is £220 to buy one so I am a bit suspicious of the garage making some extra work for themselves.

Most modern cars have a spring which acts on the clutch pedal. if some of the fingers break off on the clutch then the this spring will have enough force to keep the pedal depressed. Difficult to know for sure until gearbox is taken off

First thing is on a self adjusting hydraulic clutch if the fingers in the clutch pressure plate fail pulling up the clutch pedal by hand won't normally return the clutch to normal operation.

Start investigation from the pedal end

Check the return spring on the pedal end isn't broken (the pedal return spring is usually a torsion spring) or the pedal pivot binding.

The internal return spring in the master cylinder often breaks but first check the gearbox end.

If the clutch pressure plate is breaking up you can often detect roughness if with the engine at idle you push the fork against the pressure plate with your hand.

Check the clutch for pivots freely --- a seized clutch fork pivot is common problem on some gearboxes.

If all that is OK start checking the hydraulics.
Check the fluid level.
Observe what happens to thee fluid level when the clutch is depressed and released.
With the clutch depressed open the bleed nipple on the slave cylinder and observe what happens to the pedal and the fork.
(1) If the pedal returns it points to a fault at the slave cylinder or clutch plate or fork.
(2) If fluid flows from the bleed nipple and the clutch fork returns it points to a fault at the master cylinder end.

[Edited on 14/2/14 by britishtrident]

A really simple very first check, make sure the pedal isn't catching on the edge of mats or carpets....