"Rotten egg" type smell from interior vents

Sattyb · 07-31-2023, 11:05 AM

Hi,

I have a 2019 530i. I've noticed that when I turn on the car I get a rotten egg type smell from the air vents. This lasts for a little while and then disappears. If I press the external air button (to allow the external air in) when I start the car the smell is not as bad.

This has led me to believe that maybe it's mould etc built up in the air conditioning pipes that is causing the smell (I may be wrong but I hope someone can point me in the right direction).

I have tried activating the auxiliary ventilation when I swith the car off so the fan run when the car is switched off. This makes a little bit if difference in that the smell is nowhere as bad when I restart the car but its still there initially.

How do I getting rid of this smell?

Thanks in advance.

tjbuggy2b · 07-31-2023, 11:20 AM

Try changing your cabin air filter. If it's been a long time, it may be building up some bacteria from the organic debris it has filtered out.

Joe-BMW33 · 07-31-2023, 12:08 PM

Any chance you are losing coolant or adding coolant every month or so? Although I would not describe my issue as rotten eggs, but I was "consuming coolant" and eventually the burn off from the leak presented itself as a nose burning and eye watering smell from the vents. When the car was moving, not so bad, when stopped, it was the worst.

Had the turbo coolant lines upgraded under warranty.

Sattyb · 07-31-2023, 12:24 PM

Quote:

Originally Posted by Joe-BMW33

Any chance you are losing coolant or adding coolant every month or so? Although I would not describe my issue as rotten eggs, but I was "consuming coolant" and eventually the burn off from the leak presented itself as a nose burning and eye watering smell from the vents. When the car was moving, not so bad, when stopped, it was the worst.

Had the turbo coolant lines upgraded under warranty.

Hi, Many thanks for your replies.

My coolant level is okay and I have never had to top it up. The smell goes away after driving for around 5 mins. There is no warning light or unusual noises. Maybe, I'll try to change the cabin filter and see if that makes a difference.

Dephead2004 · 07-31-2023, 05:16 PM

You may also have to use an aerosol disinfectant on the a/c system, pipework gets. There are several threads on here with all sorts of ideas to try

Sattyb · 08-01-2023, 03:31 AM

Many thanks for all the replies and information. There are no warning lights on the dash and as the smell dissappears after around 5 mins I thought I'd check the windscreen washer fluid yesterday evening.

I opened the lid that you open to fill it and thought I'd see if I could smell anything and it was the same rotten egg smell.
I've totally emptied it, refilled and emptied again. I've them refilled and I think it may have been the cause as there is no more smell coming through.

I've started the car this morning and all seems good so i think it was the windscreen washer fluid.

Dephead2004 · 08-01-2023, 08:14 AM

Best to use a decent screencast to prevent this. I use OEM BMW stuff. Never had a problem. Never use washing up liquid unless you want your paintwork damaged.

tjbuggy2b · 08-01-2023, 11:04 PM

Wow! Never would have thought to check that.

Sattyb · 08-02-2023, 01:21 AM

Quote:

Originally Posted by tjbuggy2b

Wow! Never would have thought to check that.

I would never have thought of it either until somebody else mentioned it to me but I'd thought I'd update on here incase it helps someone else in the future.

vinniea · 09-27-2023, 01:40 AM

Quote:

Originally Posted by tjbuggy2b

Wow! Never would have thought to check that.

I would never have thought of it either until somebody else mentioned it to me but I'd thought I'd update on here incase it helps someone else in the future.

Hi Sattyb, Any update with the bad smell issue? was it resolved by draining and replacing the washer fluid?
Any idea how the washer fluid bad smell gets into the cabin? The inlet vent is behind the battery and I just don’t see the washer fluid reservoir leaking or boiling to create the bad smell.
I’ve also read that it may be the battery when this starts getting bad and cannot hold the charge it leaks, the smell is more like sulfur, as it’s been described.
Any update would be appreciated.
Thanks

23109VC · 09-29-2023, 02:02 AM

Could
You be leaking refrigerant from your evaporator ? It’s back there and they are know to go out on our cars. Is your AC blowing cold ??

vinniea · 03-04-2024, 02:02 AM

It took a while to figured out but the bad smell came from the auxiliary battery that is right in front of the air cabinet intake. This failure does not trigger an alarm, I’ve found out after reading the error codes using BimmerLink that reported the deplorable state of the auxiliary battery that measured only 2.97 volts. When the battery was draining it sent fumes that came in through the cabinet air intake.

07-31-2023, 11:05 AM	#1
Sattyb New Member 6 Rep 8 Posts Drives: 520d se Join Date: Jan 2023 Location: United Kingdom iTrader: (0)	"Rotten egg" type smell from interior vents Hi, I have a 2019 530i. I've noticed that when I turn on the car I get a rotten egg type smell from the air vents. This lasts for a little while and then disappears. If I press the external air button (to allow the external air in) when I start the car the smell is not as bad. This has led me to believe that maybe it's mould etc built up in the air conditioning pipes that is causing the smell (I may be wrong but I hope someone can point me in the right direction). I have tried activating the auxiliary ventilation when I swith the car off so the fan run when the car is switched off. This makes a little bit if difference in that the smell is nowhere as bad when I restart the car but its still there initially. How do I getting rid of this smell? Thanks in advance.
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07-31-2023, 11:20 AM	#2
tjbuggy2b Lieutenant 183 Rep 416 Posts Drives: 2018 540i xDrive M Sport Join Date: Nov 2010 Location: Columbus, OH iTrader: (0)	Try changing your cabin air filter. If it's been a long time, it may be building up some bacteria from the organic debris it has filtered out.
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07-31-2023, 12:08 PM	#3
Joe-BMW33 Major General 7338 Rep 6,749 Posts Drives: '18 M550i\|'21 X5\|'03 540i Join Date: Apr 2021 Location: Boston iTrader: (1) Garage List 2013 VW Tiguan [0.00] 2015 Infiniti QX60 [0.00] 2021 BMW X5 [0.00] 2003 BMW 540i [0.00] 2018 BMW M550 [10.00]	Any chance you are losing coolant or adding coolant every month or so? Although I would not describe my issue as rotten eggs, but I was "consuming coolant" and eventually the burn off from the leak presented itself as a nose burning and eye watering smell from the vents. When the car was moving, not so bad, when stopped, it was the worst. Had the turbo coolant lines upgraded under warranty. __________________ 2018 M550ix\|Carbon Black\|Dinan Modifications\|2003 540i\|Jet Black\|M-Sport\|2021 X5 Mineral White Prior BMW's: 1987 325e\|1993 740i\|1998 740il\|2001 530i\|2002 745li\|2007 750li\|2006 750li\|2001 530i\|2012 535xi\|
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07-31-2023, 05:16 PM	#5
Dephead2004 Lieutenant 180 Rep 548 Posts Drives: G30 520i Join Date: Feb 2018 Location: UK iTrader: (0)	You may also have to use an aerosol disinfectant on the a/c system, pipework gets. There are several threads on here with all sorts of ideas to try
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08-01-2023, 03:31 AM	#6
Sattyb New Member 6 Rep 8 Posts Drives: 520d se Join Date: Jan 2023 Location: United Kingdom iTrader: (0)	Many thanks for all the replies and information. There are no warning lights on the dash and as the smell dissappears after around 5 mins I thought I'd check the windscreen washer fluid yesterday evening. I opened the lid that you open to fill it and thought I'd see if I could smell anything and it was the same rotten egg smell. I've totally emptied it, refilled and emptied again. I've them refilled and I think it may have been the cause as there is no more smell coming through. I've started the car this morning and all seems good so i think it was the windscreen washer fluid.
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08-01-2023, 08:14 AM	#7
Dephead2004 Lieutenant 180 Rep 548 Posts Drives: G30 520i Join Date: Feb 2018 Location: UK iTrader: (0)	Best to use a decent screencast to prevent this. I use OEM BMW stuff. Never had a problem. Never use washing up liquid unless you want your paintwork damaged.
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08-01-2023, 11:04 PM	#8
tjbuggy2b Lieutenant 183 Rep 416 Posts Drives: 2018 540i xDrive M Sport Join Date: Nov 2010 Location: Columbus, OH iTrader: (0)	Wow! Never would have thought to check that.
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09-29-2023, 02:02 AM	#11
23109VC Captain 451 Rep 675 Posts Drives: 2016 X5 Join Date: Nov 2018 Location: SoCal iTrader: (0) Garage List 2018 BMW M550i [7.90] 2009 Acura TL SH-AWD [0.00] 2021 Porsche Cayenn ... [10.00]	Could You be leaking refrigerant from your evaporator ? It’s back there and they are know to go out on our cars. Is your AC blowing cold ?? __________________ Sean 2016 X5 sDrive 35i 2018 M550i
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03-04-2024, 02:02 AM	#12
vinniea New Member 2 Rep 9 Posts Drives: BMW 540i, G30 Join Date: Aug 2020 Location: Los Angeles iTrader: (0)	It took a while to figured out but the bad smell came from the auxiliary battery that is right in front of the air cabinet intake. This failure does not trigger an alarm, I’ve found out after reading the error codes using BimmerLink that reported the deplorable state of the auxiliary battery that measured only 2.97 volts. When the battery was draining it sent fumes that came in through the cabinet air intake. __________________ Vinniea
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