nick - sounds like it might be letting too much air through
Thats what I originally thought until I got my wideband fitted; 11:1 is rich
Went round to a mates to borrow an OHM meter. Turns out it was a dicky closed throttle switch.
At first it looked like the switch was shagged because when fully pressed down by the TB lever (even heard it click), there was no circuit. I pressed the micro switch further with a screw driver and it worked. With a bit of super glue & pikey engineering to the TB lever, it runs spot on now
The switch is obviously well worn (its originally a mk2 G40 TB), even adjusting the position with the two screws on the side had no effect!
Anyone know how much replacement switches are from VAG? I have a spare TB to raid if mega expensive.