turbo noise coming through cabin??
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Joined: Oct 2017
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2021 M550i
turbo noise coming through cabin??
my friend just picked up a 2021 c300 coupe right before the dealership closed last night (so will be taking it back monday morning) but in the meantime i figured i post it here on the c43 forum as i believe there is a lot of mechanical knowledge here 
so the issue is this - when pressing on the accelerator a little bit stronger there is a whoosh noise (pretty sure its the turbo) but its extremely louder than it should be but the more interesting part is you can hear it really loudly in the cabin as well.
Sounds like the noise is coming through like the window defroster area? Almost feels like a 4d disney land ride. Any ideas? did anyone else experience this? its just a loud whoooosh noise, you can hear it from the outside when the window is open and even with the windows are closed, the noise is very loud inside the cabin.
so the issue is this - when pressing on the accelerator a little bit stronger there is a whoosh noise (pretty sure its the turbo) but its extremely louder than it should be but the more interesting part is you can hear it really loudly in the cabin as well.
Sounds like the noise is coming through like the window defroster area? Almost feels like a 4d disney land ride. Any ideas? did anyone else experience this? its just a loud whoooosh noise, you can hear it from the outside when the window is open and even with the windows are closed, the noise is very loud inside the cabin.
Last edited by jhpmbusa; Jan 17, 2021 at 11:19 AM. Reason: typo
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Joined: Apr 2010
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From: Eastern Massachusetts
2021 E450, 2020 C43, 2015 C300, 2007 C280
Phony Boy-Racer Vroom-Vroom Noises
Try turning the audio system off. I had to take the Performance Exhaust (PE) on the 2020 C43 I just bought. On the way home (65 miles), I had the same reaction you and your friend had. It turns out that, even with the PE turned "off" on the center console, it still "plays" through the rear speakers -- loudly. I pulled a certain fuse in the fuse box under the trunk floor to kill the rear speakers, With the Sound Focus set to Front Seats, the sound didn't change much (and I am an audiophile). Classical music always comes from the front of the concert hall anyway.
Chances are, the phony sound effects will bypass the audio controls. (I didn't try turning the audio system off before I pulled the fuse.) Plus, you wouldn't want to kill your front speakers. This is just to give you and your friend an idea of what MB imagines your needs are and how they meet those needs, on the cheap. If your dealer won't take the car back (in Massachusetts, you get three days), all I can think of is to try an auto sound/speed shop. Be sure to look for reviews first.
Chances are, the phony sound effects will bypass the audio controls. (I didn't try turning the audio system off before I pulled the fuse.) Plus, you wouldn't want to kill your front speakers. This is just to give you and your friend an idea of what MB imagines your needs are and how they meet those needs, on the cheap. If your dealer won't take the car back (in Massachusetts, you get three days), all I can think of is to try an auto sound/speed shop. Be sure to look for reviews first.
