Audi A6/C7 2.0 TDI Ultra whistling/whirling when accelerating

[NeroRapid]

Hello dear member,

 

I own Audi A6 (C7) 2.0 TDI Ultra S-Tronic from 2016. I hear whistling/whirling sound when accelerating slowly or harder from 60 mph/70 mph at 4th, 5th, 6th or 7th gear even if I drive slower and want to accelerate this sound is hearable from front of the car. The sound comes from left/centre/front side of the car and is noticeable behind the dashboard. When I switch gear on neutral when driving is quiet also if car is stationary on parking gear to do revving nothing is happening as well. The sounds appearing only when accelerating not when revving. I also attached two files as a proof. Thank you 

[ThomasG]

Turbo whistle? Couldn't really hear much from the files. But any whistle when accelerating is usually the turbo. I can hear something, occasionally, but best to give timestamps of when it occurs.

[NeroRapid]

Hello,

The best way to hear that sound when accelerating is to use earphones but also without it whirling is noticeable in the background. I was driving on motorway with mixed surface where was some traffic. Pop up the volume as much as you can then you will find out what I mean. You right I highlight bits when I hear swirling sound. 

 

The first soundtrack:

0:06 - 0:13

1:51 - 1:56

Swirling sound is hearable in first soundtrack nearly all the time in the background but is quite because I wanted to keep the same speed to record that sound at 66mph. 

 

The second soundtrack: 

0:13 - 0:30

0:55 - 1:12

1:12 - 1:22

1:36 - 1:44

2:04 - 2:20

[Steve Q]

Definitely could be turbo or a leaking pipe from.the turbo. 

[ThomasG]

That isn't the usual turbo howl, so Steve may well be right it's a leaking pipe. 

No smoke and no loss of power mean if it is the turbo, it's not blown.

Let us know what your local garage says. You're in Coatbridge, so you could try A for Audi in Glasgow for a diagnostic.

[NeroRapid]

I was thinking it could be something related to inflow of air. Probably not enough air going in or out and this make whirrling sound hearble on the soundtrack during acceleration. Leaking pipe from turbo it can be solution because don't have smoke from exhaust, loss of power or turbo howl as well. When driving slower turbo seems to work normally also when drive at high speed everything looks good except this whirrling sound from the engine. I asked in Audi for diagnostic but they couldn't precise how long doesn't it take so I didn't wanted pay hundreds of pounds not knowing how many hours they spend on my car😉 

[OvYd3L]

Hello! How did you solve?

[NeroRapid]

Hello, unfortunately I didn't solved it yet. I guess it could be seal from turbo charger or leaking pipe. I don't want to think about faulty turbo unit because it could be so expensive to fix. 

[evopilot]

I got one of these from my SnapOn guy a few weeks ago to troubleshoot these type of problems:

https://shop.snapon.com/product/Portable-Diagnostic-Smoke-Machines/Smart-Smoke-EVAP-Machine/EELD500

If you can find somebody local to you that can run a smoke test the time paid to diagnose will save you heart ache trying to find yourself

[Gojko]

Hello NeroRapid, did you solved your problem? I guess I got same issue. Thanks 

[Steve Q]

10 hours ago, Gojko said:

Hello NeroRapid, did you solved your problem? I guess I got same issue. Thanks 

Most likely a failing turbo or turbo pipes? Check the pipes first.