"Whooshing" Noise from Engine

[oneillmobile]

Hello all,

I picked up a lovely E93 M3 yesterday, after a clean PPI and a lovely drive home. Took it out this morning and noticed a "whoosh" coming from the engine that I hadn't noticed before. I drove for about an hour, came home, and the noise was still there, and remained there later tonight when I went out for groceries.

I am still getting used to the sounds this car makes (which are incredible) and it has a full Dinan Stage 1 so a different intake and exhaust, but this noise almost sounds like a supercharger. Here is a link to the sound: https://drive.google.com/file/d/10sH...ew?usp=sharing

I can't really hear it during normal idle, but under light throttle in first and second it is noticeable.

First question: what could it be? I am leaning towards Pulleys after reading information here.

Second question: Depending on the answer to question one, how urgent is it that I get it looked at? This is a daily driver car, so not sure if this is a "deal with it ASAP' "wait a week" or "wait a month" situation.

[M3SQRD]

I didn’t hear anything odd. It could be the induction noise due to the eight ITBs coming through the Dinan intake filter. The s65 makes a lot of different noises and with time you’ll get used to them (I’m used to hearing all of the noises because I’ve had my ‘09 and ’12 since taking delivery new) so, if a new abnormal noise pops up, you should hear it.

If you’re not aware, you should read up on the rod bearing issue because the one noise you don’t want to hear is rod knock.

[oneillmobile]

Originally Posted by M3SQRD

I didn’t hear anything odd. It could be the induction noise due to the eight ITBs coming through the Dinan intake filter. The s65 makes a lot of different noises and with time you’ll get used to them (I’m used to hearing all of the noises because I’ve had my ‘09 and ’12 since taking delivery new) so, if a new abnormal noise pops up, you should hear it.

If you’re not aware, you should read up on the rod bearing issue because the one noise you don’t want to hear is rod knock.

Thank you! I specifically got this car. because the previous owner had done RB's throttle actuators, valve cover gaskets, and a few other items within 5k miles. It truly is like a symphony and I guess I am getting used to all of the different instruments!

[a5m]

Don't one of the vacuum hoses that go to the plenum leak on these cars? That noise definitely isn't normal, and don't think is part of the Dinan Intake either or ITBs.

[CTMike]

Take a look at this thread, with a cause and fix identified on page 2… like a5m mentioned, there’s some silicone that separates a bit in the plenum that can create a whistling sound. Not 100% sure that’s what you have going on but not a bad lead.

https://www.m3post.com/forums/showthread.php?t=1417824

[nick3753]

I definitely hear it in your video. When you’re at lower rpm under throttle (even light throttle) does it sound like a whistle or similar? If so, likely a hole in the back of the plenum where the air hose attaches.
Easy fix if that is the case.

https://www.m3post.com/forums/showthread.php?t=1417824

[oneillmobile]

Update for everyone:

I did an inspection of the full intake system in my throttle actuator replacement. Everything looks good there. But while running the car and checking for leaks I was able to pinpoint the sound to one of the pulleys on the passenger side of the engine.

Trying to decide if this is a DIY or Indy Shop repair. I am afraid of messing up all of those hoses in the front.