2000 Audi A4 1.8T Quattro. Had an accident, and the AT fluid mixed with the Coolant, had the tranny cleaned 3 times.

Now when cruising around 2000 RPM the transmission shifts back and forth between 2nd and 3rd and back. Very annoying.

Also, the manual mode doesn't work any more, possibly the same issue?

I really am not sure that the shop that did the original repairs didn't give us bad parts, and not even convinced that it is the original transmission anymore.

Help!