The pedal box assembly is prone to cracking along the welds and this will give the symptoms you describe, if you undo the two screws that hold the trim panel around the pedals, then with a torch have a look at the box assembly and try pressing the clutch pedal by hand you will see the joints opening up
A replacement pedal box is around £30 from VW but it aint a simple bolt in job as there are some of the fixing bolts that will need to be drilled or chisled off
nigel, June 2011
