Hi,
I have had this problem for ages and when I took it to a VW garage they couldn't find a fault!! Basically, when I'm in 3rd, 4th or 5th and put my foot on the gas, the revs go sky high and then drop back, but I don't seem to get any more speed. It is happening quite regularly now. It is almost like it is revving but there is no power there for those few seconds until it drops back to the normal level revs for the acceleration.
Any advice much appreciated - it is really beginning to hack me off!
Cheers