[div1ne]

Hi everyone,

Whenever I turn on the car there is a smell coming out of the AC that's pretty bad. The dealership told me it is because air is trapped inside and I should open some vents. I looked into it and unchecked recirculate air button and another one on iDrive. They're saying it is not the cabin filter either.

I did all that and the smell is still there. Pretty annoying to be honest, the car is 2019. Any ideas?

[Joe-BMW33]

Originally Posted by div1ne

Hi everyone,

Whenever I turn on the car there is a smell coming out of the AC that's pretty bad. The dealership told me it is because air is trapped inside and I should open some vents. I looked into it and unchecked recirculate air button and another one on iDrive. They're saying it is not the cabin filter either.

I did all that and the smell is still there. Pretty annoying to be honest, the car is 2019. Any ideas?

Can you describe the smell? Any chance it waters your eyes and burns your nose?

[LogicalApex]

Probably the gym sock smell that’s sort of common. Had it on my MB much worse and MB had a class action as a result.

It is due to mold building up in the system which happens as water doesn’t fully evaporate. It usually goes away fairly quickly on my G30 when it happens which it didn’t on the MB. That required a deep cleaning every so often.

From a maintenance perspective you can check that the car is able to drain the AC condensation. Checking water for on the ground is a good start. As when the system is running you should see water on the ground under the car. Cleaning out the lines is a regular maintenance item. Dealerships should do it during maintenance as BMW requires, but yeah…

You can also use AC disinfectant to clean it out, but I haven’t had to use this on my G30 so I doubt you should. When done on my MB it was done by MB under warranty.

[div1ne]

Yeah it's exactly gym sock. It goes away fairly quickly as well, but it's something that should not happen. Should I ask the dealership to take care of it? I still have warranty until November this year.

[LogicalApex]

Originally Posted by div1ne

Yeah it's exactly gym sock. It goes away fairly quickly as well, but it's something that should not happen. Should I ask the dealership to take care of it? I still have warranty until November this year.

You can and I haven’t yet. Let me know the outcome.

It goes away quickly enough I haven’t thought of it as an issue, but that is definitely influenced by my MB experience.

I have service coming up and will ask about it and see what happens.

[Qsilver7]

Originally Posted by div1ne

Yeah it's exactly gym sock. It goes away fairly quickly as well, but it's something that should not happen. Should I ask the dealership to take care of it? I still have warranty until November this year.

You can ask and they will probably charge you for the disinfect procedure….but maybe they won’t. Your AC stink is coming from user operation…it is not a defect in the system.

If you have a real expensive Gucci duffle bag, then put your damp towel from showering after your workout from the gym in the bag, then tossed the bag (w/towel) in your trunk…and left it there for a couple of days. Once you remember that you left the bag in the trunk…you then open the Gucci bag and get wafted with the wonderful fragrance that has bloomed as the wet towel was zipped up tight in that dark bag, left in your hot trunk, with no air circulation.

Would you accuse the Gucci bag of being defective…and claim how could a bag that cost that much smell that bad from one single wet towel? Probably not.

The same is happening with your AC system. If you are experiencing AC funk upon start up…it probably means that mold & bacteria have found a “lovers lane” condition. Are you parking in a dark area with limited air circulation after running the AC in hot temps (like a closed garage)? If yes, then try to find a way to get air circulation so that any condensate or moisture on your condenser or in your air ducts get a chance to evaporate before you close the garage door or park in a dark low air circulation area.

With the new EV models…your parked ventilation feature may have changed (your fellow model owners will have to chime in or you’ll have to look at how the option works)…but on the ICE models…BMW has a parked car ventilation feature that allows you to keep the HVAC blower running for up to 30 minutes after shutting down the car. Since it is only circulating ambient air…it doesn’t produce any further condensate and helps any excess moisture evaporate.

This feature has been on every BMW I’ve owned since the 90s (e32/e34/e38/e39/e53/f06/f15). Once I figured out that I could use the feature when I’ve been running the AC then pulling into the garage and closing the door…I have never had the AC funk issue.

Parked Car Ventilation feature on my f06 (w/CIC) & f06 & f15 (w/NBT)





The Parked Car Ventilation/Independent Ventilation feature in my e32/e34/e38/e39/e53 with the MID or OnBoard Nav system:





Auxiliary Venting (direct) on my e53 X5:

[jsf721]

Change filter for interior and spray Klima kleen.

May require more than one application and the change filters again

[LogicalApex]

Originally Posted by Qsilver7

You can ask and they will probably charge you for the disinfect procedure….but maybe they won’t. Your AC stink is coming from user operation…it is not a defect in the system.

If you have a real expensive Gucci duffle bag, then put your damp towel from showering after your workout from the gym in the bag, then tossed the bag (w/towel) in your trunk…and left it there for a couple of days. Once you remember that you left the bag in the trunk…you then open the Gucci bag and get wafted with the wonderful fragrance that has bloomed as the wet towel was zipped up tight in that dark bag, left in your hot trunk, with no air circulation.

Would you accuse the Gucci bag of being defective…and claim how could a bag that cost that much smell that bad from one single wet towel? Probably not.

The same is happening with your AC system. If you are experiencing AC funk upon start up…it probably means that mold & bacteria have found a “lovers lane” condition. Are you parking in a dark area with limited air circulation after running the AC in hot temps (like a closed garage)? If yes, then try to find a way to get air circulation so that any condensate or moisture on your condenser or in your air ducts get a chance to evaporate before you close the garage door or park in a dark low air circulation area.

With the new EV models…your parked ventilation feature may have changed (your fellow model owners will have to chime in or you’ll have to look at how the option works)…but on the ICE models…BMW has a parked car ventilation feature that allows you to keep the HVAC blower running for up to 30 minutes after shutting down the car. Since it is only circulating ambient air…it doesn’t produce any further condensate and helps any excess moisture evaporate.

This feature has been on every BMW I’ve owned since the 90s (e32/e34/e38/e39/e53/f06/f15). Once I figured out that I could use the feature when I’ve been running the AC then pulling into the garage and closing the door…I have never had the AC funk issue.

Parked Car Ventilation feature on my f06 (w/CIC) & f06 & f15 (w/NBT)





The Parked Car Ventilation/Independent Ventilation feature in my e32/e34/e38/e39/e53 with the MID or OnBoard Nav system:





Auxiliary Venting (direct) on my e53 X5:

This feature may have been removed on the G30 or PHEV G30. I'm not aware of a parked ventilation feature. You can precondition the vehicle (which will activate the AC or heater based on battery charge and ambient outside temperature) or activate the AC system while parked (on a flat battery that would ventilate, but turns off as soon as you leave and lock the car).

Perhaps BMW removed it since the AC system on the PHEV is also used to cool the battery during charging so it might run due to its own demands. I am not sure though.

That said, my experience is limited to my MY2020 so it is also possible it was removed in the iDrive 7 pathway if it does exist on a G30.

[Qsilver7]

Originally Posted by LogicalApex

This feature may have been removed on the G30 or PHEV G30. I'm not aware of a parked ventilation feature. You can precondition the vehicle (which will activate the AC or heater based on battery charge and ambient outside temperature) or activate the AC system while parked (on a flat battery that would ventilate, but turns off as soon as you leave and lock the car).

This could very well be…especially with the PHEV models…on other BMW forums where this topic has come up…the PHEV models precondition feature is as you wrote…turns on the AC…which will not help since it is creating more condensate as it dehumidifies the air in the cabin.

But if you have the regular engine…I would recommend checking if you have the old style set up like the image of the B7 below that has iDrive7 and the capability of running the HVAC blower by selecting the START NOW box (probably still requires the engine to be turned off first before it can be initiated):

{If you press the OPTION button next to the iDrive controller when you have the START NOW selected…it should give you a selection to open the owners manual to give more details about this feature}


And just to clarify…the feature above (start now) is NOT the same as the other 3 features listed on this iDrive screen. The REMOTE START and DEPARTURE features are different and may or may not start the engine…which you obviously do not want to occur if you’re parked in your closed garage.

[Genertth]

There are a few possible reasons why your car's AC might be giving off a bad smell, even when the recirculate air button is turned off.

Mold or mildew: If there is mold or mildew growing in your car's AC system, it can cause a bad smell. This can happen if the AC system is not properly maintained or if there is a leak in the system.
Leaky hose: A leaky hose can also cause moisture to build up in the AC system, which can lead to mold or mildew growth.
Dirty cabin filter: A dirty cabin filter can also cause a bad smell. The cabin filter is responsible for filtering out dust, pollen, and other particles from the air that enters the car. If the filter is dirty, it can't do its job effectively, and this can lead to a bad smell.
Blocked drain line: The AC system has a drain line that is designed to carry away any condensation that builds up. If the drain line is blocked, the condensation can build up and cause a bad smell.
If you've checked the recirculate air button and the cabin filter and the smell is still there, it's possible that one of the other causes listed above is the problem. You may need to take your car to a mechanic to have it diagnosed and repaired.

Here are some tips to help prevent a bad smell from coming from your car's AC:

Change the cabin filter regularly: The cabin filter should be changed every 12,000 to 15,000 miles, or more often if you live in a dusty or polluted area.
Keep the AC system clean: The AC system should be cleaned and serviced regularly, especially if you live in a humid climate.
Check the drain line: The drain line should be checked for blockages regularly.
Avoid using the recirculate air button: If possible, avoid using the recirculate air button. This will help to prevent moisture from building up in the AC system. https://academicpaperpros.com/reviews.php

[div1ne]

Interesting, thank you for all the info.

The car has now 20,000 miles and I got it at 14,000. I do park it inside a garage pretty much all the time. The inside of my car hasn't really had dirty clothes, just a hoodie or a vest here and there.

Once I will change the oil I will ask the dealer to look into it. I usually take pretty good care of my car and belongings in general so having that smell surprised me a little.

There is not a lot of air circulating inside my garage, but it has to grill-like openings to allow ventilation.