Does anyone have experience with this engine "whistle" sound?

from 2 perspectives -- much easier to hear from the first one:

(1)
(2)
Took to a local (but experienced) mechanic -- couldn't ID the problem. Did a full check of intake system + exhaust. No leaks . . .

Could be turbulence in the air filter and it's corresponding elbow pieces. Take the air filter out and leave the intake box open. Start your car briefly and give it a few revs to see if that eliminates it. Won't hurt to run your engine without an air filter for 10 seconds.

sounds like a possible vacuum leak.

In video #1 the whistle noise is very clear, seems like it comes from the front end of your S65 .
I would check the belt and the bearing from the pulley axle .

My engine whistles too,changed all serpentine belt pulleys and tensioners,power steering pump,different intakes and air filters and it still does it. I guess it is normal.

Damn, that’s a sick turbo you have in that m3

ciges wrote

My engine whistles too,changed all serpentine belt pulleys and tensioners,power steering pump,different intakes and air filters and it still does it. I guess it is normal.

How comparable is the sound to what I have?

The car has nearly 50k mi on it, this sound started for the first time approx. 6 weeks ago.

It seems harmless, but it is annoying as hell when driving with the windows down.

Talk2meg00se wrote

How comparable is the sound to what I have?

The car has nearly 50k mi on it, this sound started for the first time approx. 6 weeks ago.

It seems harmless, but it is annoying as hell when driving with the windows down.

Same noise,I also noticed whistle with windows down driving next to wall or building.My car has 75k now,noticed whistle 3 years ago at 55k,started replacing pulleys,tensioners,air filters ,intakes,looking for vacuum leaks,still whistles.

Snuck an S55 in there.

I have the same exact whistling noise, except it's more pronounced and I can hear it with all doors closed through the vents.

However, I have a Dinan intake installed for the past 2-3 years and the noise came with it. Probably had something to do with it. No leaks or codes thrown and car's been fine otherwise. Just a minor annoyance. Goes away either certain RPM's or speed. I forget.

Edit:
Watched the video again, except mine doesn't whistle when off acceleration. Only from ~500-1500

ciges wrote

Same noise,I also noticed whistle with windows down driving next to wall or building.My car has 75k now,noticed whistle 3 years ago at 55k,started replacing pulleys,tensioners,air filters ,intakes,looking for vacuum leaks,still whistles.

Are you running a stock filter / intake?

WingZeroX5 wrote

I have the same exact whistling noise, except it's more pronounced and I can hear it with all doors closed through the vents.

However, I have a Dinan intake installed for the past 2-3 years and the noise came with it. Probably had something to do with it. No leaks or codes thrown and car's been fine otherwise. Just a minor annoyance. Goes away either certain RPM's or speed. I forget.

Edit:
Watched the video again, except mine doesn't whistle when off acceleration. Only from ~500-1500

This sound more or less disappears when not on the gas. Most noticeable in 2nd gear between 500-2100 rpm. After that it is either drowned out or stops.

Have you tried replacing the filter?

I have an AA green filter in there. Might just replace it and see if it helps.

Talk2meg00se wrote

WingZeroX5 wrote

I have the same exact whistling noise, except it's more pronounced and I can hear it with all doors closed through the vents.

However, I have a Dinan intake installed for the past 2-3 years and the noise came with it. Probably had something to do with it. No leaks or codes thrown and car's been fine otherwise. Just a minor annoyance. Goes away either certain RPM's or speed. I forget.

Edit:
Watched the video again, except mine doesn't whistle when off acceleration. Only from ~500-1500

Have you tried replacing the filter?

I have an AA green filter in there. Might just replace it and see if it helps.

Replaced the dinan filter twice already, per normal maintenance

I have BMC air filter in mine since feb 2017 and I've heard the whistle pretty consistently with the drivers window down at low speeds 25-40 mph under low throttle input but it goes away with no throttle input.

Passengers have said it sounds like a airplane when doing pull at half throttle, at full throttle it sounds like every other V8 M3 and I don't hear the whistle.

I assume its the fact that the flow through air box with the filter in a different position or different size from the factory turns into a whistle.

I also recently developed a whistle on acceleration only. Only audible at lower rpm, likely because it gets drowned out. Numerous old threads with no solution and many users saying their cars have done it for 50+k miles. In the videos however, it sounds like yours whistles off acceleration too.

nick3753 wrote

I also recently developed a whistle on acceleration only. Only audible at lower rpm, likely because it gets drowned out. Numerous old threads with no solution and many users saying their cars have done it for 50+k miles. In the videos however, it sounds like yours whistles off acceleration too.

everything stock?

Yes

Talk2meg00se wrote

Are you running a stock filter / intake?

I have aFe carbon stage2 intake,but it has same whistle with stock filter and intake.

Mine has been whistling for a little while now, I’m at 116k. It does it when the throttle is pressed lightly.

Any correlation with the whistle and a visit to a BMW dealership for routine check-up / maintenance?

Omg, i have the same whistling....been like that for a year now.

For those that also have this whistling please do me a favor and disconnect your idle air valve tube from the plenum and then rev your car.

Does the whistling go away?

Mine does.... which leads me to believe the whistling is coming from somewhere in the idle air valve circuit.

I started a thread on this recently....no real solution but there was one comment that might lead to a solution.

gunk accumulates around the idle air valve so that it doesn't close 100% therefore causing a whistling sound.

I wanted to pull the idle air control unit out to clean it when i swapped a throttle actuator but i could not for the life of me disconnect the damn air tube without having to remove a bunch of other crap so i gave up.

If someone removes their idle air unit and cleans it and the whistling goes away let me know!


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

dreamspeed wrote

Omg, i have the same whistling....been like that for a year now.

For those that also have this whistling please do me a favor and disconnect your idle air valve tube from the plenum and then rev your car.

Does the whistling go away?

Mine does.... which leads me to believe the whistling is coming from somewhere in the idle air valve circuit.

I started a thread on this recently....no real solution but there was one comment that might lead to a solution.

gunk accumulates around the idle air valve so that it doesn't close 100% therefore causing a whistling sound.

I wanted to pull the idle air control unit out to clean it when i swapped a throttle actuator but i could not for the life of me disconnect the damn air tube without having to remove a bunch of other crap so i gave up.

If someone removes their idle air unit and cleans it and the whistling goes away let me know!


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

"gunk accumulates around the idle air valve so that it doesn't close 100% therefore causing a whistling sound"

this valve closes under acceleration?