blackoutA4

About a week ago, my 2018 S4’s turbo started to whistle more and squeal a bit when it blows off. I haven’t been able to capture the blow off, because it is somewhat occasional.

The whistle is almost too slight to hear in videos. I’m positive it did not sound like this before, was not squealing or whistling at all. Now it is doing it on every spool.

It is still spooling to max boost around 19 PSI, but the car does feel like it’s lagging a bit more than it used to.

Is slight whistling along with some squealing normal noises for these cars? I have never owned a car with audible turbos. And now I have an S4 with a CTS intake.

I asked my mechanic to inspect the turbo and he said it looks fine, but I am hesitant to believe he looked. I will try to capture better videos and update here.

blackoutA4

Bump,

https://drive.google.com/file/d/150R...w?usp=drivesdk

here is a video of the whistle. Barely audible. It’s a new sound, which is the only reason it concerns me. Otherwise, I am aware turbo whistling is normal.