View Full Version : Noise when turbos spool down.
2014 S6 with 130k miles, stock. Oil screens replaced by Audi before I bought it. I just developed an issue yesterday. I hear what sounds to me like a “whirring” or “grinding” when the turbos spool down when coming off boost. I have the lap timer screen enabled, so can see the boost gauge. If I come off throttle at steady speed when no boost showing, no noise. If I tip into the gas and see the boost gauge go up, there is a distinct noise when the boost spools down. At speeds above 50 mph, road noise covers up the sound. I brought it to my trusted Indy, who rode with me. He hears the noise, but he describes it as more of a “whooshing” and thinks it might be related to the recirculation valve that helps the turbos stay spooled up between shifts. He doesn’t think it’s bad enough to tear down the engine (might cause more problems than it fixes). He is referring me to a specific mechanic he knows at a local Audi stealership who has more experience with the 4.0T than he has. (One reason I trust him is that if he doesn’t think he knows the answer, will refer to someone else who might.) This did not gradually build up, it appeared suddenly during one specific deceleration, and is now consistently reproducible. I want to see if anyone on the forum has any experience with something similar before I go the stealership route. Thanks in advance!
BasicBlack
05-21-2023, 06:10 AM
Similar issue here. 2016 RS7, bone stock, 49K on the clock. I've had the car for 3-ish months. Good visibility to service history. Oil screen recall performed last Fall. I've heard the woosh sound since day one, mostly when driving in D, just after tipping and letting off the throttle. In my case, I'm pretty much not dipping into any boost when I hear the sound. (according to lap timer) Otherwise, car is performing pretty much to spec. No codes. But, we all know that doesn't mean a problem doesn't exist. Dealer recently replaced PCV oil seperator. Had them check the turbos while in there, all checked out ok. I get the sense your Indy is in the ball park with the diag. Very interested in the response back from your dealer tech. BTW, I'm in MA. Can always use suggestions for trustworthy Indy's. All the best.
Alabama
05-21-2023, 08:37 AM
I want to see if anyone on the forum has any experience with something similar before I go the stealership route. Thanks in advance!
Posting a video with audio may help the experts here.
I’m in the Merrimack Valley north of the city and go to Euro Car Center in Wilmington. Don, the owner, is an Audi mechanic trainer. Was referred to him by a friend and have only had positive experiences with him.
BasicBlack
05-21-2023, 02:42 PM
I’m in the Merrimack Valley north of the city and go to Euro Car Center in Wilmington. Don, the owner, is an Audi mechanic trainer. Was referred to him by a friend and have only had positive experiences with him.
Great to know. Metro West here. I'll definately consider the recommendation. Thanks so much. Please keep us posted on your quest to solve the "woosh".
Enjoy the ride.
Bsharp
05-23-2023, 07:05 PM
On my S7 I added the holes in the corner of the airbox like the RS7 has, after I did that the whoosh was very audible.You should check for proper airbox connection and the condition of the rubber hose connection to the turbo inlets.