As it says, if I change up at high engine speeds, the clutch pedal doesn't fully return sometimes, yet the clutch itself is fully engaged and not slipping.

When it happens I can lift it back with my foot and it's ok.

Any ideas? Master cylinder(vacuum) or clutch related?

Cheers
D

 

It happens to me as well...Usually when the pedal gets stuck behind the footwell mat during quick shifts...