Rumble/buzz at certain rpm

nuclearbeef · 03-28-2019, 10:59 AM

I have kind of a rumble or buzz at a certain rpm when accelerating.
It sounds like a loose piece of exhaust or heat shield or something like that.

Before I go rooting around looking for loose items, does anyone have any suggestions for other things to look at?

I have 225k miles and am on my original engine mounts. No clunk when turning, but I thought that they might be a culprit also. Anyone experienced my symptoms with worn mounts?

Thanks,

JW

335dlci · 03-28-2019, 12:14 PM

Yes.

MDeeJs · 03-29-2019, 02:13 PM

I had similar issue and it was the engine cover. It was not fully in a place and the plastic was touching other stuff around. Fixed it and then started to hear the damn RF tyres. New tyres and it's all quiet again

nuclearbeef · 03-29-2019, 04:35 PM

I've been driving it for the last 2 days without the engine cover and the noise, if anything, is louder.
The engine mounts show no sign of metal to metal contact like I've seen others post pictures of when they collapse.
I'm still leaning towards heat shield.
I have other irons in the fire at the moment.
After 30k-40k miles of no trouble, I've replaced the harmonic balancer; throttle assembly and glow plug controller all in the last 1k miles.
On the way home today, the brake light came on yellow and the anti-lock yellow caution came on as well.

lnxguy · 03-30-2019, 10:53 AM

Wheel bearing. My passenger side rear went and I swore the sound was coming from right under the drivers seat. Definitely not like any other dead wheel bearing I've had on previous cars. Almost sounds like rocks in a tincan. I thought it was the heat shield as well.

nuclearbeef · 04-05-2019, 10:27 PM

Quick update.
After pulling codes, new rear left wheel speed sensor fixed all warnings.
Bearing felt good.
Surprisingly, the sensor had no marks on it from the reluctor ring. Installed new sensor and it did not touch the reluctor ring either.

So, back to the original problem. I pulled up next to a brick wall (with the window down so I could hear) and reved the car in park. It makes the noise right at 1500 rpm. Noise is not coming from any parts that are not moving while the car is in park.

Probably a loose exhaust/engine part.
I did recently replace the harmonic balancer with the fluid damper unit along with the clutched alternator pulley. I definitely didn't notice the noise immediately after installation, but maybe one of those parts has gone bad?

I'll get under there at some point and see what I find.

Owen81 · 04-10-2019, 08:43 AM

When did you order your Fluidampr? There was a recall on a batch of those, Andrew sent out an email to all those affected.

Just because your mounts aren't clicking yet doesn't mean they aren't worn. They slowly collapse over time so I would replace those regardless at your mileage.

aaddam2 · 04-12-2019, 08:04 PM

i noticed that same sound only in cold temps and typically at 1200 rpm, summer time i dont hear it at all.

nuclearbeef · 07-03-2019, 04:45 PM

Update...
FIXED

I knew I was going to Atlanta for work in June, so I just waited until I got there and took it to AARodriguez. He did my tunes/deletes, so I trusted them to do it right.

It was a heat shield. The front (top?) 2 tack welds on the downpipe heat shield had broken. A quick weld and all is fixed!!!

Also replaced thermostat, pax engine mount, and got the ATM intake.
Don't know if it is any faster, but certainly less smoke at full throttle, so I'm happy.

(yes, I know it's not a throttle)

03-28-2019, 10:59 AM	#1
nuclearbeef Private 8 Rep 54 Posts Drives: 2010 335d Join Date: Jun 2014 Location: Memphis iTrader: (0)	Rumble/buzz at certain rpm I have kind of a rumble or buzz at a certain rpm when accelerating. It sounds like a loose piece of exhaust or heat shield or something like that. Before I go rooting around looking for loose items, does anyone have any suggestions for other things to look at? I have 225k miles and am on my original engine mounts. No clunk when turning, but I thought that they might be a culprit also. Anyone experienced my symptoms with worn mounts? Thanks, JW
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03-28-2019, 12:14 PM	#2
335dlci Lieutenant Colonel 277 Rep 1,574 Posts Drives: 335d Join Date: Apr 2014 Location: Socal iTrader: (0)	Yes.
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03-29-2019, 02:13 PM	#3
MDeeJs Martin 24 Rep 51 Posts Drives: 435i, 335d, 2x35d Join Date: Aug 2015 Location: Sykesville, MD iTrader: (0)	I had similar issue and it was the engine cover. It was not fully in a place and the plastic was touching other stuff around. Fixed it and then started to hear the damn RF tyres. New tyres and it's all quiet again
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03-29-2019, 04:35 PM	#4
nuclearbeef Private 8 Rep 54 Posts Drives: 2010 335d Join Date: Jun 2014 Location: Memphis iTrader: (0)	I've been driving it for the last 2 days without the engine cover and the noise, if anything, is louder. The engine mounts show no sign of metal to metal contact like I've seen others post pictures of when they collapse. I'm still leaning towards heat shield. I have other irons in the fire at the moment. After 30k-40k miles of no trouble, I've replaced the harmonic balancer; throttle assembly and glow plug controller all in the last 1k miles. On the way home today, the brake light came on yellow and the anti-lock yellow caution came on as well.
	Appreciate 0 Quote

03-30-2019, 10:53 AM	#5
lnxguy Lieutenant Colonel 357 Rep 1,723 Posts Drives: 2009 335D Join Date: Jun 2016 Location: Barrie iTrader: (1)	Wheel bearing. My passenger side rear went and I swore the sound was coming from right under the drivers seat. Definitely not like any other dead wheel bearing I've had on previous cars. Almost sounds like rocks in a tincan. I thought it was the heat shield as well. __________________ '09 335D
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04-05-2019, 10:27 PM	#6
nuclearbeef Private 8 Rep 54 Posts Drives: 2010 335d Join Date: Jun 2014 Location: Memphis iTrader: (0)	Quick update. After pulling codes, new rear left wheel speed sensor fixed all warnings. Bearing felt good. Surprisingly, the sensor had no marks on it from the reluctor ring. Installed new sensor and it did not touch the reluctor ring either. So, back to the original problem. I pulled up next to a brick wall (with the window down so I could hear) and reved the car in park. It makes the noise right at 1500 rpm. Noise is not coming from any parts that are not moving while the car is in park. Probably a loose exhaust/engine part. I did recently replace the harmonic balancer with the fluid damper unit along with the clutched alternator pulley. I definitely didn't notice the noise immediately after installation, but maybe one of those parts has gone bad? I'll get under there at some point and see what I find.
	Appreciate 0 Quote

04-10-2019, 08:43 AM	#7
Owen81 Lieutenant 83 Rep 432 Posts Drives: 335d, 17/22 TDI Join Date: May 2015 Location: Alberta, Canada iTrader: (0)	When did you order your Fluidampr? There was a recall on a batch of those, Andrew sent out an email to all those affected. Just because your mounts aren't clicking yet doesn't mean they aren't worn. They slowly collapse over time so I would replace those regardless at your mileage.
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04-12-2019, 08:04 PM	#8
aaddam2 Private First Class 32 Rep 153 Posts Drives: '11 e90 335d M-Sport Join Date: Apr 2016 Location: Chicago, IL iTrader: (0)	i noticed that same sound only in cold temps and typically at 1200 rpm, summer time i dont hear it at all.
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07-03-2019, 04:45 PM	#9
nuclearbeef Private 8 Rep 54 Posts Drives: 2010 335d Join Date: Jun 2014 Location: Memphis iTrader: (0)	Update... FIXED I knew I was going to Atlanta for work in June, so I just waited until I got there and took it to AARodriguez. He did my tunes/deletes, so I trusted them to do it right. It was a heat shield. The front (top?) 2 tack welds on the downpipe heat shield had broken. A quick weld and all is fixed!!! Also replaced thermostat, pax engine mount, and got the ATM intake. Don't know if it is any faster, but certainly less smoke at full throttle, so I'm happy. (yes, I know it's not a throttle)
	Appreciate 1 robnitro160.00 Quote