Vibration & chattering sound at idle

Virology · 07-19-2023, 06:58 PM

I drive a 2009 BMW 328i xDrive N51 engine w/ the 6 speed manual transmission @ 160,000 miles. I'm noticing a 'rumble/vibration' while at idle, whether I've just started the engine or when I come to a stop at a red light. I can feel the vibration through the driver's seat and in the steering wheel. The engine doesn't display any actual running issues and drives normal. The idle is steady at 700~ RPM with no dips or surging. If I rev the engine to about 1k RPM the vibration and chattering stops.

I replaced spark plugs about 3 months ago (no coils yet), engine is full of oil, and no warning lights active. Scanning the DME with my Autel only showed one DTC: '002AAC - Variable Intake System 2, self diagnosis'. The code was in absent status, I cleared it and hasn't come back. I'm not seeing any misfires or other unusual data while the car is idling or while driving.

I can only feel the rumbling and hear the chattering while I'm sitting in the car and don't hear anything abnormal under the hood.

The car has also always made a similar sort of chattering/clank sound whenever I shut off the engine, I read somewhere a while back that this could be due to the flywheel and is normal? but I'm not entirely sure. I wonder if that could be related at all?

I've read through the forums and watched some videos but haven't found anything exactly matching what I have going on. I'd appreciate if anyone out there has some insight! I'm going to inspect the engine and transmission mounts tomorrow to make sure they aren't causing it.

Thank you

Phil325i · 07-20-2023, 08:44 AM

I suspect you'll be on the right track with failed mounts...

sabino56 · 07-20-2023, 03:15 PM

I have 2006 with ~160k miles. I've had two instances of noisy/rough idle problems.
One was a bad motor mount.
Another was a bad overrunning pulley on the alternator.
both ~easy to check. Good luck!

Virology · 07-20-2023, 07:43 PM

Quote:

Originally Posted by sabino56

I have 2006 with ~160k miles. I've had two instances of noisy/rough idle problems.
One was a bad motor mount.
Another was a bad overrunning pulley on the alternator.
both ~easy to check. Good luck!

Thanks for the reply. Pulleys were another thing I was questioning but didn't see any abnormal play or sound coming from any of them. Upon inspecting for possible mount movement, I verified the chattering noise was internal at the bell housing/transmission. Pressing clutch pedal in would quiet it down pretty much completely from underneath the vehicle.

Discovered the entire problem is due to the dual mass flywheel and release bearing being worn like I questioned in the original post, which makes sense after 160,000 miles on I believe original parts. I wasn't knowledgeable of the common symptoms of a DMF until doing more research. Will be installing a clutch kit and new DMF!

Jelle458 · 07-23-2023, 01:27 PM

Not to highjack or anything, but it seems like I have an identical problem, and it seems like you found a solution.

I do not hear any clank sounds, only when the engine starts it does a pretty big CLONK-like sound.

Other than that I feel the rumble in my seat, it's a tiny shaking when idle, but is also felt at around 3000 rpm.

I also noticed touching the exterior of the car when engine is idle I can feel the shaking pretty hard. Putting a foot on a rim and I also feel shaking here.

I did have a problem with a broken engine mount, but I replaced it with a new and original but it didn't help the the shaking.

Though I am "only" at around 130.000 miles this could be the issue, but are you able to confirm that you also feel a small shaking when touching the exterior of your car?
Mine is 330i so I guess the behaviour would be kinda the same.

Jelle458 · 08-05-2023, 08:36 AM

So no one answered, but I'd like to follow-up for anyone coming here.

It definitely was the dual mass flywheel that did this. All it's grease was all over the gearbox, but never hit the clutch.
I got a full original LUK dual mass flywheel kit which also includes clutch, pressure plate, bolts, pressure bearing and arm. Since I was there I replaced engine mounts and gearbox mounts, and also many parts of the gearshift was replaced with new.

It's a completely different car. It runs a lot smoother, and I have no shaking inside the car, or when touching it.

I had same problem as this guy:
https://www.e90post.com/forums/showp...3&postcount=25
https://www.e90post.com/forums/showp...2&postcount=29
https://www.e90post.com/forums/showp...8&postcount=30

Torque specs were very easy to find using google while doing the job. I used a total of 8 hours doing the replacement, but this is also with taking it slow, a small dinner break, and fitting the gearbox twice. First time I couldn't get the top bolt in so had to take the full gearbox down to make sure the bolt would actually fit.

I also have a hoist available, along with two 1000kg gearbox lifters that go really high. One for tipping the engine, and one for supporting the gearbox while taking it off and on.

Really not a lot of space for anything, but got it done and really happy with the results.

07-19-2023, 06:58 PM	#1
Virology Registered 2 Rep 2 Posts Drives: BMW 328i Join Date: Jul 2023 Location: Kentucky iTrader: (0)	Vibration & chattering sound at idle I drive a 2009 BMW 328i xDrive N51 engine w/ the 6 speed manual transmission @ 160,000 miles. I'm noticing a 'rumble/vibration' while at idle, whether I've just started the engine or when I come to a stop at a red light. I can feel the vibration through the driver's seat and in the steering wheel. The engine doesn't display any actual running issues and drives normal. The idle is steady at 700~ RPM with no dips or surging. If I rev the engine to about 1k RPM the vibration and chattering stops. I replaced spark plugs about 3 months ago (no coils yet), engine is full of oil, and no warning lights active. Scanning the DME with my Autel only showed one DTC: '002AAC - Variable Intake System 2, self diagnosis'. The code was in absent status, I cleared it and hasn't come back. I'm not seeing any misfires or other unusual data while the car is idling or while driving. I can only feel the rumbling and hear the chattering while I'm sitting in the car and don't hear anything abnormal under the hood. The car has also always made a similar sort of chattering/clank sound whenever I shut off the engine, I read somewhere a while back that this could be due to the flywheel and is normal? but I'm not entirely sure. I wonder if that could be related at all? I've read through the forums and watched some videos but haven't found anything exactly matching what I have going on. I'd appreciate if anyone out there has some insight! I'm going to inspect the engine and transmission mounts tomorrow to make sure they aren't causing it. Thank you
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07-20-2023, 08:44 AM	#2
Phil325i Brigadier General 616 Rep 3,194 Posts Drives: E92 325i MSport Coupe Join Date: Apr 2012 Location: UK South East iTrader: (1) Garage List 2009 BMW 325i Coupe [6.00]	I suspect you'll be on the right track with failed mounts... __________________ E92 pre-LCI 325i - Ohlins R&T; H&R spacers; M3 strut brace; Swift thrust sheets; 3 x chassis braces; diff brace; N53 V-brace; 034 subframe inserts; BMS clutch stop; BMS CDV; RE g/box mounts; Delrin shift bushes; Saikoumichi OCC; Cyba scoops; BMW Perf Exhaust; HEL s/steel brake hoses; M3 rear spoiler; Recaro Sportster CSs; M3 white dash LEDs; LED Angels; LED side repeaters; BMW Perf black grille; CSL reps; SSDD carbon diffuser; Monster Wrap black roof/clear front
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07-20-2023, 03:15 PM	#3
sabino56 Private First Class 76 Rep 134 Posts Drives: 2006 E90 330i Join Date: Mar 2018 Location: AZ, Tucson iTrader: (0)	I have 2006 with ~160k miles. I've had two instances of noisy/rough idle problems. One was a bad motor mount. Another was a bad overrunning pulley on the alternator. both ~easy to check. Good luck!
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07-23-2023, 01:27 PM	#5
Jelle458 New Member 12 Rep 29 Posts Drives: 330i E90 Join Date: Aug 2021 Location: Denmark iTrader: (0)	Not to highjack or anything, but it seems like I have an identical problem, and it seems like you found a solution. I do not hear any clank sounds, only when the engine starts it does a pretty big CLONK-like sound. Other than that I feel the rumble in my seat, it's a tiny shaking when idle, but is also felt at around 3000 rpm. I also noticed touching the exterior of the car when engine is idle I can feel the shaking pretty hard. Putting a foot on a rim and I also feel shaking here. I did have a problem with a broken engine mount, but I replaced it with a new and original but it didn't help the the shaking. Though I am "only" at around 130.000 miles this could be the issue, but are you able to confirm that you also feel a small shaking when touching the exterior of your car? Mine is 330i so I guess the behaviour would be kinda the same.
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08-05-2023, 08:36 AM	#6
Jelle458 New Member 12 Rep 29 Posts Drives: 330i E90 Join Date: Aug 2021 Location: Denmark iTrader: (0)	So no one answered, but I'd like to follow-up for anyone coming here. It definitely was the dual mass flywheel that did this. All it's grease was all over the gearbox, but never hit the clutch. I got a full original LUK dual mass flywheel kit which also includes clutch, pressure plate, bolts, pressure bearing and arm. Since I was there I replaced engine mounts and gearbox mounts, and also many parts of the gearshift was replaced with new. It's a completely different car. It runs a lot smoother, and I have no shaking inside the car, or when touching it. I had same problem as this guy: https://www.e90post.com/forums/showp...3&postcount=25 https://www.e90post.com/forums/showp...2&postcount=29 https://www.e90post.com/forums/showp...8&postcount=30 Torque specs were very easy to find using google while doing the job. I used a total of 8 hours doing the replacement, but this is also with taking it slow, a small dinner break, and fitting the gearbox twice. First time I couldn't get the top bolt in so had to take the full gearbox down to make sure the bolt would actually fit. I also have a hoist available, along with two 1000kg gearbox lifters that go really high. One for tipping the engine, and one for supporting the gearbox while taking it off and on. Really not a lot of space for anything, but got it done and really happy with the results.
	Appreciate 1 Phil325i615.50 Quote