[Oda6]

Hey guys,

I’m new here, I just bought my 2021 M2C MT w/ 10k miles a week ago. Car drives flawlessly with zero issues in drive ability. A couple days ago I noticed the car makes a rattling/chattering sound while idling, if you press in the clutch the sound goes away and when you release it you can hear it again. It typically only does this after being fully warmed up. The sound isn’t always present but seems to be more frequent when releasing the clutch quickly. Most of the time it’s not very loud either. If you are sitting at the light and it’s not making the sound, pumping the clutch once or twice might induce it. Some times when idling it doesn’t make the sound at all.


Is this just normal flywheel sounds that the car makes or should I be concerned?
Is this something many others experience?


Car is a single owner CPO w/ 10k miles and Manual transmission. Car drives and looks very clean. I have made an appointment for service in a few days but wanted to do some additional research.

Thanks for your help

[Oda6]

Originally Posted by MoM2C

From my experience with other cars, the symptoms you are describing is usually an indication of an issue with the input shaft bearings.

Ughhh that’s what I feared. Damn.

[DarthFader]

Mine has been doing that since day 1

Currently just over 60k miles and it still drives like new

[TSLM]

Oda6 do you hear this noise during clutch take-up? As in, from a stop, slowing letting the clutch out with normal throttle input for takeoff?

[Oda6]

Originally Posted by TSLM

Oda6 do you hear this noise during clutch take-up? As in, from a stop, slowing letting the clutch out with normal throttle input for takeoff?

No only when idling. When I first got the car a week ago I heard it a couple times when first starting to move but I think that was because I wasn’t giving it enough gas. That was day one. Since I’ve gotten use to the clutch I have not heard that since. Seems like that was technique.

So to answer your question, no I’m only hearing it during idle.

[Oda6]

Originally Posted by DarthFader

Mine has been doing that since day 1

Currently just over 60k miles and it still drives like new

Okay that’s more reassuring. I had read that other people experience it without negative side effects. Hopefully it’s just the sound the DMF makes at times.


Thanks!!

[Kosta1968]

There are some posts about the exhaust cam head bolts being loose and needing replacement to fix the issue. Do a search for it.

[Suhb]

My understanding is that this is dual mass flywheel chatter. My M2 at 34k miles has it. My 128i had it around 40k miles. It never affected the car adversely up until 150k miles when I sold it.

BMW told me the noise was normal operating noise when I took it in under warranty. From my understanding it's a widespread noise from the DMFW in BMWs in general.