[NGT2]

Some may remember I had a rattling sound coming from the front of my 2018 540. I took it in and they thought they heard it too. They disassembled and retightened some suspension components under warranty and away I went. I do think it made a difference, so that part is fine, and I got a once over on my suspension before factory warranty ran out (now under CPO).

Current issue - Some of the same rattling is still there. Most prevalent in the morning, especially if it's cold. This isn't the sunroof or the seatbelt or the headrest or from the A/C. It's also not the normal creaking noises that come from plastic in the dash. This is a defined rattle that's caused by slight imperfections in the road, mostly at low speeds. I notice it leaving for work, driving through the neighborhood.

It is definitely from the driver side dash area. It absolutely sounds like plastic on plastic, definitely not metal on metal. Tomorrow I will try again putting pressure on some areas around the dash screen, the HUD, and the pillar that runs from the roof to the dash. I noticed you can move that pillar away from the dash a bit if you press on it slightly.

If it's not something surface level, all I can think is some plastic parts have become a little loose with time. I have had an ambient light strip replaced and had parts of the A/C replaced. Perhaps they removed part of the dash for one of those repairs and this is the result. If that's the case, it makes sense it would show up in the cold, with the plastic hardening and contracting in the cold temps overnight and then expanding and softening as the car warms up, therefore the noise being less prevalent throughout the day.

Sorry for such a long description. Has anyone had a dull plastic sounding rattle in the dash?

I'll mention it at my next service, but wanted to ask here again, also. Thanks for any feedback on experience or ideas!

[Mosaud1998]

Originally Posted by NGT2

Some may remember I had a rattling sound coming from the front of my 2018 540. I took it in and they thought they heard it too. They disassembled and retightened some suspension components under warranty and away I went. I do think it made a difference, so that part is fine, and I got a once over on my suspension before factory warranty ran out (now under CPO).

Current issue - Some of the same rattling is still there. Most prevalent in the morning, especially if it's cold. This isn't the sunroof or the seatbelt or the headrest or from the A/C. It's also not the normal creaking noises that come from plastic in the dash. This is a defined rattle that's caused by slight imperfections in the road, mostly at low speeds. I notice it leaving for work, driving through the neighborhood.

It is definitely from the driver side dash area. It absolutely sounds like plastic on plastic, definitely not metal on metal. Tomorrow I will try again putting pressure on some areas around the dash screen, the HUD, and the pillar that runs from the roof to the dash. I noticed you can move that pillar away from the dash a bit if you press on it slightly.

If it's not something surface level, all I can think is some plastic parts have become a little loose with time. I have had an ambient light strip replaced and had parts of the A/C replaced. Perhaps they removed part of the dash for one of those repairs and this is the result. If that's the case, it makes sense it would show up in the cold, with the plastic hardening and contracting in the cold temps overnight and then expanding and softening as the car warms up, therefore the noise being less prevalent throughout the day.

Sorry for such a long description. Has anyone had a dull plastic sounding rattle in the dash?

I'll mention it at my next service, but wanted to ask here again, also. Thanks for any feedback on experience or ideas!

I also noticed a rattle noise when it's cold out and I'm driving home. But, not sure where it's coming from. I do have an appt. with my local BMW dealership to check over a bunch of stuff before my factory warranty expires next year.

[BMW012]

as the temp drops so does the tire pressure. so different creaks occur, but thats just a side note. not saying that's the cure.

[Joe-BMW33]

These rattles can be annoying and once you hear them, you can't un-hear them!

Do this. Have your wife drive around the neighborhood and intentionally hit the uneven spots that cause the rattle. You sit in the passenger seat with you ear all over it. If need be, put the seat all the way back and get on the floor and listen. Try to zero in on the area it is coming from and go from there. I did this on my E39. I started in the backseat and made my way to the front passenger and found the issue under the dash. I started in the back because I would have bet the house it was coming from behind the passenger seat. These noises can be tricky in terms of location. They often are not coming from the area you hear from the drivers seat.

[CnSky]

Have you tried holding the plastics that surround the rear view mirror and cameras. I had a rattle that sounded like it was from the dash but ended up it was this area, a loose cover.

[NGT2]

Originally Posted by CnSky

Have you tried holding the plastics that surround the rear view mirror and cameras. I had a rattle that sounded like it was from the dash but ended up it was this area, a loose cover.

I'll give it a try. But I don't think that's it.

This morning I drove multiple times over all the bumps that trigger it and held down different surface areas around the dash, etc. None made a difference. I'm positive that it's coming through the dash and is below the surface.

I will check the wheel wells tonight to be sure it's not something loose there that is traveling up through the dash area.

[CnSky]

Originally Posted by NGT2

I'll give it a try. But I don't think that's it.

This morning I drove multiple times over all the bumps that trigger it and held down different surface areas around the dash, etc. None made a difference. I'm positive that it's coming through the dash and is below the surface.

I will check the wheel wells tonight to be sure it's not something loose there that is traveling up through the dash area.

I thought the same that it was coming from behind the dash or in the air ducts but ended being the mirror camera covers. Hope it's same for you.

It sounded like a buzzing rattle for me and was all dependent on surfaces and temperature.

[NGT2]

Originally Posted by CnSky

I thought the same that it was coming from behind the dash or in the air ducts but ended being the mirror camera covers. Hope it's same for you.

It sounded like a buzzing rattle for me and was all dependent on surfaces and temperature.

Thanks - I will definitely check that.

I feel like "rattle" isn't even a good descriptor for this. It sounds more like how it might sound if an AC vent was fit loosely and bounced around within its housing. Just like plastic banging plastic. Or a piece of plastic being bounced around in a box.

Crazy how difficult it is to describe these kinds of things.

[NGT2]

IF YOU DO NOT WANT TO READ THE EXPLANATION PLEASE SKIP TO THE PRIMARY QUESTION AT THE END.

I may have found it. I can't upload the videos here because I don't have a YouTube account or know how to use any hosting sites. But I did include a picture of the area in question.

I believe this is simply a rain gutter. If so, I was thinking I could soften it with some felt tape or something similar where the pieces meet. The gutter runs horizontal across the car, below the windshield. It feeds into these two chutes that turn downward and fit into two vertical tubes running down on either side of the car. Where the horizontal gutter feeds to the vertical chute, it's like a male to female connection. THIS is the place where I think the cold plastic pieces are getting jostled and bumping, causing a rattle that flows into the cabin.

I have taken video of the noise in action. I also turned my video camera (iPhone) on and laid it on the dash, and then closed the door and jostled these pieces. The resulting noise from in the cabin, captured on video, sounds like it's the same sound. It was a little louder when I duplicated it by hand, but that makes sense since there was no road noise and my hand probably creates more pronounced movement than the bumps on the road.

PRIMARY QUESTION: Is the piece in question, pictured below, simply a rain gutter? If so, would I be risking anything by just putting some kind of felt layer there to soften the noise and impact between the pieces where they meet?

Thanks for any input!

[Joe-BMW33]

Originally Posted by NGT2

IF YOU DO NOT WANT TO READ THE EXPLANATION PLEASE SKIP TO THE PRIMARY QUESTION AT THE END.

I may have found it. I can't upload the videos here because I don't have a YouTube account or know how to use any hosting sites. But I did include a picture of the area in question.

I believe this is simply a rain gutter. If so, I was thinking I could soften it with some felt tape or something similar where the pieces meet. The gutter runs horizontal across the car, below the windshield. It feeds into these two chutes that turn downward and fit into two vertical tubes running down on either side of the car. Where the horizontal gutter feeds to the vertical chute, it's like a male to female connection. THIS is the place where I think the cold plastic pieces are getting jostled and bumping, causing a rattle that flows into the cabin.

I have taken video of the noise in action. I also turned my video camera (iPhone) on and laid it on the dash, and then closed the door and jostled these pieces. The resulting noise from in the cabin, captured on video, sounds like it's the same sound. It was a little louder when I duplicated it by hand, but that makes sense since there was no road noise and my hand probably creates more pronounced movement than the bumps on the road.

PRIMARY QUESTION: Is the piece in question, pictured below, simply a rain gutter? If so, would I be risking anything by just putting some kind of felt layer there to soften the noise and impact between the pieces where they meet?

Thanks for any input!

I think I would start with treating the rubber with something to moisten, soften or lubricate it. I think CarPro Perl is in your toolbox.

[NGT2]

@Joe-BMW33 that is a good thought - but these are plastic pieces coming together. I don't think the rubber parts of the gutter are making any noise

[CnSky]

I forgot that I had the exact same issue last year have an old post on here about it somewhere.

I removed the gutter on both sides and the two plastic covers for accessing the areas on right and left of the engine bay in the same area and used loads of felt where parts meet. Worked my way down along the gutter as it drops into the bay.

Sorted it 100% never came back.

I can send photos if you PM me of what I did and where.

[NGT2]

Originally Posted by CnSky

I forgot that I had the exact same issue last year have an old post on here about it somewhere.

I removed the gutter on both sides and the two plastic covers for accessing the areas on right and left of the engine bay in the same area and used loads of felt where parts meet. Worked my way down along the gutter as it drops into the bay.

Sorted it 100% never came back.

I can send photos if you PM me of what I did and where.

Hell yeah! That's awesome. Thanks for confirming that, it makes me feel less insane. I looked for similar posts but sometimes they aren't easy to find.

I will PM you ASAP.

[Wiving]

I got same problem tryna figure out where its coming from

[Ultron2023]

Originally Posted by CnSky

I forgot that I had the exact same issue last year have an old post on here about it somewhere.

I removed the gutter on both sides and the two plastic covers for accessing the areas on right and left of the engine bay in the same area and used loads of felt where parts meet. Worked my way down along the gutter as it drops into the bay.

Sorted it 100% never came back.

I can send photos if you PM me of what I did and where.

Hi, do you still have the photos of what you did to fix the problem please? I think my 5 series has a similar issue.

Thanks

[CnSky]

Sold the car sorry can’t take photos.

[Warp Ten]

"Cheer up", she said, "Things could get worse". So I cheered up and, sure enough, things got worse". --Bob