Strange air-conditioner noise

delete-this-account · 11-25-2011, 11:26 PM

hey all,
2006 130i auto..

When I have my air conditioner running, there's a strange squeaking/rattling noise coming from inside the cabin behind the dash. It gets louder under braking (even gentle braking or deceleration), and goes away when i turn the air-conditioner off - even if i leave the fan on (just turn the compressor off).

It's quite loud and driving me (and my passengers) insane.
I've searched the internets to no avail - most responses are regarding the compressor or belts itself. My noise is definitely coming from within the cabin.

Any one else experienced something similar?

Many thanks

thunderb · 11-30-2011, 03:42 AM

I have a 2005 Build 130i and I would say have almost the exact same problem, and had been told it would cost approx $1500 to pull the dash apart to investigate. Not for a resolution just to investigate, so I've put up with it for 18 months so far.

We thought it might have been a leaf stuck somewhere, so pulled the the cover off under the bonnet and gave it a good blow out with an air hose and tried to dislodge the leaf, it went away for a couple of days and was a lot quieter for a couple of weeks.

But the strange thing is that my noise goes away under gentle acceleration or braking and only happens when it coasts etc...

To me it kind of sounds like a fan has a bearing that is on its way out and by speeding up / slowing down a little it just changes the spinning axis of the fan a touch and puts it on/off axis a little. But really i've got no idea on what I'm talking about.

delete-this-account · 11-30-2011, 03:02 PM

thanks thunder..
Sounds like the same problem, i think it's a fan bearing also.. but can't work out where the fan would be. doesn't matter if the air conditioner is blowing on feet, face, or windscreen, the noise still happens..
i agree it must be a bit loose so deceleration or coasting causes it to make the noise.

Was that BMW that told you $1500? I might try BMW as well as a BMW specialist somewhere. surely it can't cost $1500 just to take the dash out? they must have lawyers working on it at that hourly rate...

thunderb · 12-03-2011, 06:46 AM

Yes it was Toowoomba BMW.

Dackelone · 12-03-2011, 08:06 AM

Does it sound like a cow moo-ing? That kind of noise is usually the AC expansion valve in the bulkhead where the evaperator hoses go thru the firewall. Usual fix is to replace the expansion valve AND make sure there is the correct amount of freon in the ac system.

thunderb · 12-04-2011, 07:57 AM

Thanks,
Mine doesn't sound like a cow moo-ing, but they could sound different up side down in Germany

It definitely sounds like a fan bearing, but after 18 months its no better or worse, and the AC is on whenever the vehicle is running. I clock about 25 000 km per year so the AC gets a workout.

So after 18 months I would have expected it to get better or worse if it were in fact a fan bearing, which is why I haven't done too much about it.

Just turn the music up a little more, I really wish I had an amp and some of those SW8 earthquakes to hide the hideous sound better.

Chris1337 · 05-02-2019, 01:09 PM

ever figure out the issue? got the strange noise when braking with A/C on

11-25-2011, 11:26 PM	#1
delete-this-account Private 7 Rep 98 Posts Drives: DD Join Date: Sep 2009 Location: DD iTrader: (0)	Strange air-conditioner noise hey all, 2006 130i auto.. When I have my air conditioner running, there's a strange squeaking/rattling noise coming from inside the cabin behind the dash. It gets louder under braking (even gentle braking or deceleration), and goes away when i turn the air-conditioner off - even if i leave the fan on (just turn the compressor off). It's quite loud and driving me (and my passengers) insane. I've searched the internets to no avail - most responses are regarding the compressor or belts itself. My noise is definitely coming from within the cabin. Any one else experienced something similar? Many thanks __________________ 130i m-sport
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11-30-2011, 03:42 AM	#2
thunderb Enlisted Member 0 Rep 35 Posts Drives: BMW 130i Join Date: Jul 2011 Location: Toowomba, QLD, AUS iTrader: (0)	I have a 2005 Build 130i and I would say have almost the exact same problem, and had been told it would cost approx $1500 to pull the dash apart to investigate. Not for a resolution just to investigate, so I've put up with it for 18 months so far. We thought it might have been a leaf stuck somewhere, so pulled the the cover off under the bonnet and gave it a good blow out with an air hose and tried to dislodge the leaf, it went away for a couple of days and was a lot quieter for a couple of weeks. But the strange thing is that my noise goes away under gentle acceleration or braking and only happens when it coasts etc... To me it kind of sounds like a fan has a bearing that is on its way out and by speeding up / slowing down a little it just changes the spinning axis of the fan a touch and puts it on/off axis a little. But really i've got no idea on what I'm talking about.
	Appreciate 0 Quote

11-30-2011, 03:02 PM	#3
delete-this-account Private 7 Rep 98 Posts Drives: DD Join Date: Sep 2009 Location: DD iTrader: (0)	thanks thunder.. Sounds like the same problem, i think it's a fan bearing also.. but can't work out where the fan would be. doesn't matter if the air conditioner is blowing on feet, face, or windscreen, the noise still happens.. i agree it must be a bit loose so deceleration or coasting causes it to make the noise. Was that BMW that told you $1500? I might try BMW as well as a BMW specialist somewhere. surely it can't cost $1500 just to take the dash out? they must have lawyers working on it at that hourly rate... __________________ 130i m-sport
	Appreciate 0 Quote

12-03-2011, 06:46 AM	#4
thunderb Enlisted Member 0 Rep 35 Posts Drives: BMW 130i Join Date: Jul 2011 Location: Toowomba, QLD, AUS iTrader: (0)	Yes it was Toowoomba BMW.
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12-03-2011, 08:06 AM	#5
Dackelone European Editor 10532 Rep 22,992 Posts Drives: N54 e82 Join Date: Feb 2010 Location: Bayern, Germany iTrader: (1)	Does it sound like a cow moo-ing? That kind of noise is usually the AC expansion valve in the bulkhead where the evaperator hoses go thru the firewall. Usual fix is to replace the expansion valve AND make sure there is the correct amount of freon in the ac system.
	Appreciate 0 Quote

12-04-2011, 07:57 AM	#6
thunderb Enlisted Member 0 Rep 35 Posts Drives: BMW 130i Join Date: Jul 2011 Location: Toowomba, QLD, AUS iTrader: (0)	Thanks, Mine doesn't sound like a cow moo-ing, but they could sound different up side down in Germany It definitely sounds like a fan bearing, but after 18 months its no better or worse, and the AC is on whenever the vehicle is running. I clock about 25 000 km per year so the AC gets a workout. So after 18 months I would have expected it to get better or worse if it were in fact a fan bearing, which is why I haven't done too much about it. Just turn the music up a little more, I really wish I had an amp and some of those SW8 earthquakes to hide the hideous sound better.
	Appreciate 0 Quote

05-02-2019, 01:09 PM	#7
Chris1337 First Lieutenant 27 Rep 290 Posts Drives: 2012 e92 335i Join Date: Apr 2017 Location: Miami, FL iTrader: (0)	ever figure out the issue? got the strange noise when braking with A/C on
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