Hi there.
I'm new to Audis but we have just bought an A4 1.8T auto convertible. It's a beautify can but I think there is something wrong with the auto. Is fine trundling round town but on faster roads we have a problem. If I put my foot down when we are cruising at, say, 40mph the revs will rise from c1800rpm to 5,000 but we get very little acceleration. Overtaking is virtually impossible and accelerating up hill is impossible.

What could be the problem and what might the cost of repair be??

Many thanks in advance. Any suggestions very much appreciated.