rattle at idle

portlandareae28 · 05-17-2019, 11:18 AM

Hello, I am new to the N54 but not BMW, my car recently started making a rattle that I could hear at idle when the A/C is on. Sounds like a loose heat shield and when under the hood sounds more like it is coming from underneath the airbox or oil filter housing than from the front of the car belt, tensioner, pulley, etc.. It doesn't make the noise until the car is warm (viscosity issue somewhere?) and also immediately goes away if you increase RPM. I am going to do an oil change this weekend and may pull the whole belly just to have a look when I do the oil change. Any thoughts would be greatly appreciated.. I did put my stethoscope on the tensionser pulley and 2 others that I can easily get to and don't hear anything abnormal on them, of course it could be a pulley that I can't get to.. I am happy to try and post the video somewhere if it will help.

Thank you in advance for any ideas.

rawdog573 · 05-17-2019, 11:43 AM

check the metal skid plate underneath the oil pan. my bolts were loose when i first bought mine.

Chappers 71 · 05-17-2019, 11:45 AM

How many miles has it done?
I would say that the most likely candidates are waste gate rattle, that comes from drivers side low down by the front wheel, could be injector tick which is normal.
It will rattle from the exhaust flap, this is closed on start up which rattles & it opens once the cars been running a for a couple of minutes or so, then the rattle stops but that comes from the passenger side at the back.

I would say it's most likely gonna be the waste gates rattling.
Welcome to 35i ownership

portlandareae28 · 05-17-2019, 11:57 AM

the noise is high not low, what about the disa valve? anyone dealt with one? car has 115k on it. I have done the rev test for Wastegates, doesn't seem to have any noise on the rev test.

Chappers 71 · 05-17-2019, 12:29 PM

At that mileage if the turbos haven't been replaced they will have waste gate rattle.
I've never read of anyone posting about disa valve issues on a n54.

portlandareae28 · 05-17-2019, 12:46 PM

hmmmmm... where it sounds to me like the noise is isolated is between the air box, oil filter housing, and valve cover. It sounds like a rattle and less like it is rotating but I am no expert by any means. I don't know that the rattle is the valve it self or maybe the pieces that the valve controls. I am going to listen closer again tonight, I don't and won't drive the car until this is solved. Ultimately I just don't want to throw parts at it, its not a car that I need to drive everyday so I want to take my time, isolate, learn and fix.

mweisdorfer · 05-17-2019, 12:50 PM

Quote:

Originally Posted by portlandareae28

the noise is high not low, what about the disa valve? anyone dealt with one? car has 115k on it. I have done the rev test for Wastegates, doesn't seem to have any noise on the rev test.

335 doesn't have a DISA valve

Chappers 71 · 05-17-2019, 12:58 PM

Quote:

Originally Posted by mweisdorfer

335 doesn't have a DISA valve

portlandareae28 · 05-17-2019, 01:10 PM

well good, that is not my problem than :-) :-) :-)

I will check for heat shield rattles this weekend, but the fact that cold it doesn't do it and warm it does, and the a/c plays a role too gets my brain thinking something more complicated than a heat shield rattling. My wife says she feels it in the floor of the drivers compartment so maybe it is lower than it sounds..

portlandareae28 · 05-17-2019, 02:22 PM

Quote:

Originally Posted by rawdog573

check the metal skid plate underneath the oil pan. my bolts were loose when i first bought mine.

thank you, this is the first place I will check once I pull the belly off.

portlandareae28 · 05-17-2019, 02:24 PM

Quote:

Originally Posted by Chappers 71

At that mileage if the turbos haven't been replaced they will have waste gate rattle.
I've never read of anyone posting about disa valve issues on a n54.

Will the waste gates just rattle at idle and go away with higher rpm even with no load? Would the A/C being turned on and or off have an effect on this?

MadDog89 · 05-17-2019, 02:46 PM

anyway you can post a video?

portlandareae28 · 05-17-2019, 03:02 PM

I have video in my phone, let me see if I can convert it to youtube and post a link.

portlandareae28 · 05-17-2019, 03:12 PM

mweisdorfer · 05-17-2019, 03:36 PM

Quote:

Originally Posted by portlandareae28

Quote:

Originally Posted by Chappers 71

At that mileage if the turbos haven't been replaced they will have waste gate rattle.
I've never read of anyone posting about disa valve issues on a n54.

Will the waste gates just rattle at idle and go away with higher rpm even with no load? Would the A/C being turned on and or off have an effect on this?

No. The fan turns on & off with the AC. I'd start there.

portlandareae28 · 05-17-2019, 03:39 PM

Quote:

Originally Posted by mweisdorfer

No. The fan turns on & off with the AC. I'd start there.

I have unplugged the fan thinking the same thing and it didn't change anything.

Chappers 71 · 05-17-2019, 06:28 PM

There's the usual injector tick but that other noise sounds like a rumbling bearing, possibly alternator?
The noise in the vids doesn't sound like wg rattle, that would be more of tinkling kinda noise when you first start the car

MadDog89 · 05-17-2019, 08:36 PM

Almost sounds like hallow plastic vibrating against something.

My other car (not a BMW) had a similar sound, it was a blower motor that needed to be replaced.

portlandareae28 · 05-17-2019, 09:28 PM

Quote:

Originally Posted by MadDog89

Almost sounds like hallow plastic vibrating against something.

My other car (not a BMW) had a similar sound, it was a blower motor that needed to be replaced.

Blower motor for interior Hvac?

swilke0393 · 05-18-2019, 04:49 PM

I've sort of the same problem. Cant post yet.

2007 328Xi

A couple of days ago I was changing parking spaces
and the engine cut off on me. Idling hard. Turned
out to be misfiring on 1 3 and 4.

Changed all the plugs and coils.
Eccentric Shaft? was changed a few thousand miles ago.

also had a N1415 code.

But its still idles rough a little at start,
jumping between 12 and 4 RPMS 1 or two times..
then settling around 5 after a couple minutes.

MadDog89 · 05-19-2019, 04:31 PM

Quote:

Originally Posted by portlandareae28

Blower motor for interior Hvac?

Yes

portlandareae28 · 06-17-2019, 06:21 PM

pulled the belly pan off this weekend, found some oil of course

and 2 bolts missing from the power steering pump. Amazing the belt hasn't shredded already. Luckily I don't drive it much normally, and since the noise I haven't been driving it at all.. I am not sure I have figured out the best path to the rear bolt yet, but I will be doing the filter housing at the same time. I am so far understanding the intake manifold has to be at least moved to do the filter housing. Since I don't know how long the filter housing has been leaking, will likely want to pull the alternator and clean that whole area. Please offer any wisdom on making the job easier, and keeping the ps pump bolts in place long term?

05-17-2019, 11:18 AM	#1
portlandareae28 New Member 1 Rep 27 Posts Drives: 335i Join Date: Dec 2018 Location: Inland Empire iTrader: (0)	rattle at idle Hello, I am new to the N54 but not BMW, my car recently started making a rattle that I could hear at idle when the A/C is on. Sounds like a loose heat shield and when under the hood sounds more like it is coming from underneath the airbox or oil filter housing than from the front of the car belt, tensioner, pulley, etc.. It doesn't make the noise until the car is warm (viscosity issue somewhere?) and also immediately goes away if you increase RPM. I am going to do an oil change this weekend and may pull the whole belly just to have a look when I do the oil change. Any thoughts would be greatly appreciated.. I did put my stethoscope on the tensionser pulley and 2 others that I can easily get to and don't hear anything abnormal on them, of course it could be a pulley that I can't get to.. I am happy to try and post the video somewhere if it will help. Thank you in advance for any ideas.
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05-17-2019, 11:43 AM	#2
rawdog573 Second Lieutenant 37 Rep 233 Posts Drives: bmw 335xi Join Date: May 2019 Location: missouri iTrader: (0)	check the metal skid plate underneath the oil pan. my bolts were loose when i first bought mine.
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05-17-2019, 11:45 AM	#3
Chappers 71 Major General 5483 Rep 5,422 Posts Drives: Beige G31 40ix m sport Join Date: Feb 2016 Location: Kent, The Garden of England iTrader: (0) Garage List 2018 G31 xdrive 40i ... [4.00] 2006 E92 335i SE [9.50]	How many miles has it done? I would say that the most likely candidates are waste gate rattle, that comes from drivers side low down by the front wheel, could be injector tick which is normal. It will rattle from the exhaust flap, this is closed on start up which rattles & it opens once the cars been running a for a couple of minutes or so, then the rattle stops but that comes from the passenger side at the back. I would say it's most likely gonna be the waste gates rattling. Welcome to 35i ownership __________________ G31 40ix M Sport E92 335i. E36 328is coupe E39 540i V8 6SP manual E34 3.6 M5. E34 525i sport. VW Jetta Mk2 GTI 16v. 1679cc 1967 resto-cal beetle Last edited by Chappers 71; 05-17-2019 at 11:54 AM..
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05-17-2019, 11:57 AM	#4
portlandareae28 New Member 1 Rep 27 Posts Drives: 335i Join Date: Dec 2018 Location: Inland Empire iTrader: (0)	the noise is high not low, what about the disa valve? anyone dealt with one? car has 115k on it. I have done the rev test for Wastegates, doesn't seem to have any noise on the rev test. Last edited by portlandareae28; 05-17-2019 at 12:01 PM.. Reason: better description
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05-17-2019, 12:29 PM	#5
Chappers 71 Major General 5483 Rep 5,422 Posts Drives: Beige G31 40ix m sport Join Date: Feb 2016 Location: Kent, The Garden of England iTrader: (0) Garage List 2018 G31 xdrive 40i ... [4.00] 2006 E92 335i SE [9.50]	At that mileage if the turbos haven't been replaced they will have waste gate rattle. I've never read of anyone posting about disa valve issues on a n54. __________________ G31 40ix M Sport E92 335i. E36 328is coupe E39 540i V8 6SP manual E34 3.6 M5. E34 525i sport. VW Jetta Mk2 GTI 16v. 1679cc 1967 resto-cal beetle
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05-17-2019, 12:46 PM	#6
portlandareae28 New Member 1 Rep 27 Posts Drives: 335i Join Date: Dec 2018 Location: Inland Empire iTrader: (0)	hmmmmm... where it sounds to me like the noise is isolated is between the air box, oil filter housing, and valve cover. It sounds like a rattle and less like it is rotating but I am no expert by any means. I don't know that the rattle is the valve it self or maybe the pieces that the valve controls. I am going to listen closer again tonight, I don't and won't drive the car until this is solved. Ultimately I just don't want to throw parts at it, its not a car that I need to drive everyday so I want to take my time, isolate, learn and fix.
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05-17-2019, 01:10 PM	#9
portlandareae28 New Member 1 Rep 27 Posts Drives: 335i Join Date: Dec 2018 Location: Inland Empire iTrader: (0)	well good, that is not my problem than :-) :-) :-) I will check for heat shield rattles this weekend, but the fact that cold it doesn't do it and warm it does, and the a/c plays a role too gets my brain thinking something more complicated than a heat shield rattling. My wife says she feels it in the floor of the drivers compartment so maybe it is lower than it sounds..
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05-17-2019, 02:46 PM	#12
MadDog89 Second Lieutenant 52 Rep 250 Posts Drives: 2007 335i E92 Join Date: Apr 2019 Location: California iTrader: (0)	anyway you can post a video?
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05-17-2019, 03:02 PM	#13
portlandareae28 New Member 1 Rep 27 Posts Drives: 335i Join Date: Dec 2018 Location: Inland Empire iTrader: (0)	I have video in my phone, let me see if I can convert it to youtube and post a link.
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05-17-2019, 03:12 PM	#14
portlandareae28 New Member 1 Rep 27 Posts Drives: 335i Join Date: Dec 2018 Location: Inland Empire iTrader: (0)
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05-17-2019, 06:28 PM	#17
Chappers 71 Major General 5483 Rep 5,422 Posts Drives: Beige G31 40ix m sport Join Date: Feb 2016 Location: Kent, The Garden of England iTrader: (0) Garage List 2018 G31 xdrive 40i ... [4.00] 2006 E92 335i SE [9.50]	There's the usual injector tick but that other noise sounds like a rumbling bearing, possibly alternator? The noise in the vids doesn't sound like wg rattle, that would be more of tinkling kinda noise when you first start the car __________________ G31 40ix M Sport E92 335i. E36 328is coupe E39 540i V8 6SP manual E34 3.6 M5. E34 525i sport. VW Jetta Mk2 GTI 16v. 1679cc 1967 resto-cal beetle
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05-17-2019, 08:36 PM	#18
MadDog89 Second Lieutenant 52 Rep 250 Posts Drives: 2007 335i E92 Join Date: Apr 2019 Location: California iTrader: (0)	Almost sounds like hallow plastic vibrating against something. My other car (not a BMW) had a similar sound, it was a blower motor that needed to be replaced.
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05-18-2019, 04:49 PM	#20
swilke0393 Registered 0 Rep 3 Posts Drives: 2007 BMW 328Xi Join Date: May 2019 Location: Southeast USA iTrader: (0)	I've sort of the same problem. Cant post yet. 2007 328Xi A couple of days ago I was changing parking spaces and the engine cut off on me. Idling hard. Turned out to be misfiring on 1 3 and 4. Changed all the plugs and coils. Eccentric Shaft? was changed a few thousand miles ago. also had a N1415 code. But its still idles rough a little at start, jumping between 12 and 4 RPMS 1 or two times.. then settling around 5 after a couple minutes.
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06-17-2019, 06:21 PM	#22
portlandareae28 New Member 1 Rep 27 Posts Drives: 335i Join Date: Dec 2018 Location: Inland Empire iTrader: (0)	pulled the belly pan off this weekend, found some oil of course and 2 bolts missing from the power steering pump. Amazing the belt hasn't shredded already. Luckily I don't drive it much normally, and since the noise I haven't been driving it at all.. I am not sure I have figured out the best path to the rear bolt yet, but I will be doing the filter housing at the same time. I am so far understanding the intake manifold has to be at least moved to do the filter housing. Since I don't know how long the filter housing has been leaking, will likely want to pull the alternator and clean that whole area. Please offer any wisdom on making the job easier, and keeping the ps pump bolts in place long term?
	Appreciate 0 Quote