This is the bain of my life right now!!
So far my 100 has managed to leave me stranded 4 times
Is your clutch pedal coming back up?
If not most likely slave or master cylinder, try to bleed the system (im presumming yours will be like mine) at the passenger side calliper NOT to bleed nipple on the slave cylinder this will have no effect!
I have replaced the slave cylinder in mine in november, then the master cylinder went last month, then the slave cylinder went again! thankfully the second time it was covered by warenty as a genuine part fitted at a main dealers.
If your replacing one of the cylinders do the other as well as if one has worn out chances are the other has as well
