REPOST - RPM rough at idle

[audinoob45]

I am reposting the same thing due to no replies.. hopefully someone else will see it this time and reply.

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

[creativecody]

Link is broken.

[Sick S4]

I have been experiencing this as well. Not as bad as yours though, mine will jump up to about 1100 RPM and then search between there and 850. Hasn't effected drivability and goes away after I drive it for a few minutes when I put it back into park.

[audinoob45]

LINK REPOSTED..

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

[audinoob45]

I have been experiencing this as well. Not as bad as yours though, mine will jump up to about 1100 RPM and then search between there and 850. Hasn't effected drivability and goes away after I drive it for a few minutes when I put it back into park.

I heard some bad things about it being the pistons or the coils.. so im just cautious. better safe than sorry

[BlownOne]

That's really weird...have you changed anything recently? Check your air filter and replace or clean if necessary. Unhook your battery for a few hours then reconnect to reset the Ecu and see if that helps.

[bwizard]

Seems like you got water in an electrical connector some where. Ecu,coils,maf,map,injecors

Sent from my S4's talk to text @ a buck thirty

[audinoob45]

That's really weird...have you changed anything recently? Check your air filter and replace or clean if necessary. Unhook your battery for a few hours then reconnect to reset the Ecu and see if that helps.

I got my timing chain tensioner replaced from the audi dealership, thats a pretty big job. other than that, no. I took it through that same car wash today and it didnt do anything to the car this time. I wonder if it was a misfire.

When the audi techs were taking out the engine, i asked them to look out for anything else that needed replacing, and they said that everything was fine inside. So im not sure. Im new to Supercharged cars so im kinda lost haha

[audinoob45]

Im going to clean out my cia when i have a day free. And change my oil. havent done that since i got the car. (2k miles ago)