So I got my audi s4 b8.5 a couple months ago and i love it. Today i took it through the car wash and put it in Park while the car wash was doing its job. I noticed my idle started to jump ip and down from 650-1100. After i got out of the wash, i drove it around and it was driving fine. Then when i parked in front of my drive way again and put it in park. It started doing the same thing.. thats when i took the video. In the video, i rev the car 3 times. Other than that, the car is doing that by itself. After about 10 minutes of having the car off, i turned it back on and it stopped doing it. It drove fine, and even in park, it was fine.. could it have been the water? a leak? any ideas?

Link to video..
https://drive.google.com/open?id=0B3...3g4bnk3cERFcDg