Audi A3 Whistle Noise: BLS Engine, 2006

I'm hearing a whistling noise on my BLS. I thought it might be coming from the AGR cooler, specifically where the shaft is for the switching mechanism, and that it might be a leak. However, when I hold my hand there, I don't feel anything.
"When the engine is idling, you can barely hear anything. If you disconnect the EGR valve, you can hear it even at idle. Of course, you can also hear it when you accelerate. When driving and the turbocharger is under more load, the noise becomes much, much louder."
I then checked the intake side of the turbocharger, but there was no axial play, and I didn't see any signs of wear or scoring.
I'm not 100% sure if the noise is actually coming from the turbo, and replacing it based on suspicion is a bit expensive. I also found a technical service bulletin (TPI) where the exhaust hanger (device carrier) is changed from metal to plastic to address whistling noises.

Does anyone recognize this sound?

Your video is gone?!?

Quote:

I also found a technical information bulletin where the material of the exhaust bracket (device carrier) is changed from metal to plastic to eliminate whistling noises.

What TPI?
Do you have it?
Part numbers for the replaced parts?

Greetings.
m;

2012959/3

1K0 253 144 BC

chli1976 wrote:

1K0 253 144 BC

Based on the description, I suspected that was the part.

But what about the __WHISTLE__?
How does that work?

I'm now more inclined to suspect that the noise is coming from the BLS (Blockheizkraftwerk/Combined Heat and Power unit) and I'll just replace it to see if that fixes it.

m;