Hi, part of the specification on my A4 TFSi 252PS is MHEV. I have been trying to figure something out since I purchased the car, second-hand, as follows. When I'm driving along at say 70mph the rev counter is showing approximately 2,000rpm. If I lift my foot off the throttle, sometimes nothing happens except of course the speed begins to drop, other times the autostop cuts in and the car coasts along, all fair enough. However, other times the revs drop back to around 700/800rpm with the speed still around the 70mph mark - what is actually happening here I continually wonder, so decided to ask on here as I have no doubt some of you very knowledgeable folk will be able to help me out. Thanks for reading.