Whistling sound upon acceleration

[WingZeroX5]

Originally Posted by Talk2meg00se

RE-READ:Unless you really know what you're doing, this is not a DIY.

No.

Nonetheless, removing the plenum is the easiest thing.

So, this is so a DIY

[Redd]

Whistling sound had been bothering me for a good year or so. Finally go around to taking off the plenum and applying RTV silicone to the ICV inlet like in the pictures. Whistle is now gone! Woohoo!

[luckyse7en]

I have this whistling sound too. Has anyone else besides Talk2meg00se been able to get their plenum replaced under federal emissions warranty?

I would like to get the plenum replaced if it is covered under warranty. But with only one user having this done under warranty doesn't give me high hopes this will be covered.

I don't want to spend the money on diagnostics and such if the dealer decides to just blow me off and charge me for a new plenum and labor.

[nyc_dude]

High mileage E9x M3s will spring an oil filter housing leak. Rubber gasket becomes brittle, just like the valve cover gaskets, which are prone to leaks. Oil hits the belts and they make noise.

The idler pulleys have bearing that wears out and causes the whistling to, like a supercharger. The hydraulic tensioners also fail. So change it all when you change the belts.

Good to know that the plenum can cause the whistling sound. Fun way to fix that is to get a custom painted M3 S65 plenum from IND, and return your core. Great Price!!! Can't wait for my TVAs to fail, so I can do this...HaHa.

https://ind-distribution.com/collect...3-engine-cover

If you have a E9x or F8x M3 in LA, there are great Indie Shops to visit vs. BH BMW.

The Federal EPA 8 yr/80k mile Warranty covers your TVAs and ICV, but no BMW Dealership SA will tell you that....especially if your BMW warranty has expired.

UPDATE: Whistling was still there after the oil filter housing and pulleys/tensioner/belts were replaced in Feb. 2020.
ICV and Fuel Tank Breaker Valve were replaced in Dec. 2019. Defective ICV/FTBV causes jumpy idle and not the whistling sound. I also have the Eventuri Carbon Fiber Intake and Airbox Cover that I installed in mid-2019, which resonates nicely, but doesn't cause the whistling sound. Unless you have a supercharger, the plenum ICV hose inlet is the likely source of the whistling that changes with accelerator position. Also check that each of the 8 throttle body rubber gaskets/hoses is properly seated under the plenum. If not seated properly or brittle, the plenum will crush the rubber piece and cause a leak (BMW Dealer did this once).

UPFATE2: The whistling sound can be recreated by driving on the street at 30-55 mph in top gears 4-5-6-7, then take your foot off the accelerator and then back on while reving the engine from 1000-2000 rpm. Then you can hear the whistling. You won't hear the whistling at highway speeds at 2500-3000 rpm.

A new S65 plenum is $1100-1300, plus $120 for the //M V8 emblems. Try to find a low mileage used one on ebay or deans bimmer or your local BMW Indie Shop, if you don't want to try the RTV leak fix.

Darn...a Custom Painted IND S65 Plenum was sooooo close. https://www.m3post.com/forums/showthread.php?t=528247

dreamspeed just saved me a ton of $$$$. Thank you!!!

Cheers

[nullobjective]

Thanks so much for this write up. I just got my 2013 M3 and it has the whistling sound as described. I cant hear it as much when just revving stationary (probably due to being in garage and hearing more exhaust than anything) - but I definitely only get it when moving the pedal position.

I want to run the quick test of disconnecting the idle air tube on the back of the plenum... but I cant get it to budge. I see the black/plastic clamps you are talking about, but they don't seem to let loose of anything when squeezing them. Any ideas?


Adding a photo (attached). That is what I have been focusing on.

[dvici]

Originally Posted by nullobjective

Thanks so much for this write up. I just got my 2013 M3 and it has the whistling sound as described. I cant hear it as much when just revving stationary (probably due to being in garage and hearing more exhaust than anything) - but I definitely only get it when moving the pedal position.

I want to run the quick test of disconnecting the idle air tube on the back of the plenum... but I cant get it to budge. I see the black/plastic clamps you are talking about, but they don't seem to let loose of anything when squeezing them. Any ideas?


Adding a photo (attached). That is what I have been focusing on.

My car had the exact same noise and the reason was that this bracket was not propperly attached. After reinstalling the plenum I was not capable of getting this bracket to "click". Any tips? I was pushing up very hard but didn't succeed...

[nullobjective]

Originally Posted by dvici

My car had the exact same noise and the reason was that this bracket was not propperly attached. After reinstalling the plenum I was not capable of getting this bracket to "click". Any tips? I was pushing up very hard but didn't succeed...

Just got mine finished up today as a Saturday quarantine project

The attachment to the plenum didn't click when taking it off or putting it back on for me, and everything seems to be fine.

No more whistling after applying the RTV to the spot dreamspeed mentioned. Kudos!

I could basically make a tune with my sound and the pedal position, was super annoying.

[m7mad]

This really helped thanks all for sharing everything useful.

I have been experiencing the whistle since I got the car which was a year ago.
I actually did not think it was this easy, just need to take your time removing the plenium, took me around an hour to disassemble and apply RTV and put everything back.

One thing shocked me was how dirty things are underneath the plenium.

[hackR]

dreamspeed

thank you!...this fixed my whistling!...appreciate your assistance!!!

[itsnotme]

Thank you. I will give this a try. I've had this issue for over a year now.

[nick3753]

How long did you guys wait after applying the RTV? I attempted the repair this am while changing plugs (for the first time). I saw the hole in the inlet and applied RTV the best I could to try to fill it. It probably sat another 1.5 hours while I did the plugs and struggled to get the plenum back on (that damn hose in the back is a bitch). Went for a ride and at first thought it was fixed, but after maybe 2 minutes it came back. I'm not sure if I didn't wait long enough for it to cure, or if my whistle is just more obvious once the engine warms a bit? As much as it pisses me off, hopefully I was just too impatient and can attempt it again in a few months when I'm due for a new air filter.

[rogi16012]

Thank you for this! My 2012 started whistling about a year ago and I didn't realize how much of a nuisance it was until this fix. Solved the whistling completely. I let the RTV dry for 24 hours before starting the car back up. Used this thread for the step by step directions to access the plenum: https://www.m3post.com/forums/showthread.php?t=1273927

[GinTonic]

Thank you to the poster who suggested using RTV silicone. Had this issue for the past 9-12 months but never did anything about it. Since it was warm yesterday, I took the plenum off and tried this trick. The noise is finally gone!

[FrznM3]

The best product to use for this is The Right Stuff. It dries within 15 minutes. I’ve had to do an emergency oil pan repair on my 350z in the past where I used this and had the car filled with oil 10 minutes after I screwed the oil pan on.