My M3P has been troubled with mostly wind and road noise originating from areas or in ways that don't seem right since I got it 1 year ago. I've been at my local service center 4 times with the issues, and every time they make it worse, so I decided to try and fix it myself.
For the past few months I've spent almost every weekend of free time in a combination of driving trying to locate the issue areas, going back home to fix, going out again in what seems like an almost endless cycle without really great results. It's gotten better for sure, but I still have issues, particularly with the frameless windows and/or A-pillars. Unfortunately I've run out of ideas -- and the ones I've already tried might also not be the best since I lack expertise and go solely by gut feeling.
What I have done so far (basic stuff):
- Mounted extra door seals in all doors (BASENOR Mode 3 Door Seal Kit)
- Mounted frunk and trunk isolation mats from Torque Alliance
- Replaced floor/frunk/trunk mats with 3dmaxspider
- Added rpm tesla wind noise reduction kit
Combined these made a noticeable difference - mostly in reduced road noise, and less dirt on the insides (bonus).
To fix wind noise I've tried fiddling with the window seals. The first thing I noticed was that inner piece didn't seal tight against the windows in several places. This was concluded by sliding a plastic applicator from a vinyl kit between the window and seal:
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I also found that the outer-most rubber that contacts the window (the part to the right of the plastic tool, under the widow, just before the center glass piece) had gaps in some places so it also didn't make window contact. My logic tells me that this is not right, and that the way to fix it is to either push the windows further inwards or push the seals outwards. I read that windows can be tilted inwards by screws behind the door panels, but I couldn't find any videos on how to do this and decided to try and fix it the other way (this may be a wrong decision?).
I've inserted D-type door seals behind the seal liner itself to push it out (on all 4 windows, this only shows the back):
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I also added B-type door seals behind the inner flap to push it outwards (sorry the shots are from different sides, hope it's still clear):
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These changes made a significant difference to the noise coming from the back parts of the windows. What I can't figure out now is where the remaining noise is coming from. There's normal wind noise coming from the windshield of course, but there's also a kind of rustling noise that's especially apparent with strong side winds. It sounds like it's coming from the upper part of the window/seals. However, even though there are some areas here that are not perfectly tight against the window, I'm not sure that's the issue though since the window seals tight against the seal on the top. This is one of the problematic areas due to bulging in the seal:
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The upper part of the window seal is much stiffer than the back part, and it doesn't seem possible to insert anything under the seal itself or the (large) inner flap to push it out.
Another potential source of issues could be the triangle pieces next to the side mirrors. It sounds like some wind noise is coming from here as well but I'm not sure how to fix it. The triangles don't seem to be sticking out enough to cause noise, as I've seen on some M3s.
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I also tried adding B-type seals to different positions on the inside of the door, to make the door shut tighter against the triangle/plastic piece. This helped a little, but the noise is still not eliminated.
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Any ideas on how to improve here is greatly appreciated.
I hope some kind souls could share ideas for how to fix the remaining noise. If not, then at least I hope you can use my approach above to eliminate some of your own.
