Hey guys, new to the forum so I apologize if this has already been covered. I have a 2011 A4 2.0t manual. 60k miles... Just recently the car started squealing once it's warmed up. Really loud, high pitched constant squealing.. It does stop making noise under acceleration but, as soon as I lift off the gas it starts up again. Car seems to be running fine, but does get a little choked up during idle. Has anyone experienced this in their car or have any idea what the problem may be? I really appreciate your help

 

Open the hood while the engine is running , try & remove the oil cap. If is difficult then you have a bad crankcase vent valve. You will have excessive crankcase vacuum making it hard to pull off.

 

Also getting an iat cel.

 

Yes you will! You are getting unfettered air inside the engine. Most likely fuel trim codes.

 

No problem taking off the oil cap... Any other suggestions to explain this loud squealing and cel ?

 

Could be the high pressure pump starting to fail. You are going to have to get the fault codes stored at this point.

 

If you are in a cold environment , could it be as simple as an auxiliary belt slipping?