Bad smell from heater/AC in my 2008 E91

[current]

Hi folks.
I have a problem with a bad smell that comes from the heater or AC in my 2008 E91 320i. It smells like cowshit and it appears from tme to time.
I have tried AC cleaner but it didn't help. I took out the microfilter/carbonfilter and tried to locate the smell from it, but I couldn't smell anything from it. Have ordered a new one anyway.
Is there someone that have an idea what it is and how to get rid of it?

[BimmerBreaker]

Once the cabin filters are replaced it should go away

[sreilly]

Cabin air filter

[spoonerDee]

Replacing the cabin air filter does not always remedy the problem. It's a common issue in e46's and is a result of mildew that builds up inside the ducts from moisture getting stuck inside while using the A/C. A few members have solved the problem by spraying a cleaner/disinfectant or something of the sorts in the exterior intake part of the vents. Remove the air filter turn the fans on high (with all your windows open) and spray vigorously.

There is a DIY on it I believe, google, e46 duct smell fix or something of the sort.

[current]

Thanks! I hope it will.

- - - Updated - - -

Replacing the cabin air filter does not always remedy the problem. It's a common issue in e46's and is a result of mildew that builds up inside the ducts from moisture getting stuck inside while using the A/C. A few members have solved the problem by spraying a cleaner/disinfectant or something of the sorts in the exterior intake part of the vents. Remove the air filter turn the fans on high (with all your windows open) and spray vigorously.

There is a DIY on it I believe, google, e46 duct smell fix or something of the sort.

I suspected it could be something like that. I will follow your advice. Thanks!

[current]

Once the cabin filters are replaced it should go away

Thanks!

[current]

Once the cabin filters are replaced it should go away

Lets hope it will. It smells like a farm.

[BimmerBreaker]

If the cabin air filter doesnt fix it, spooner touched on what the real problem could be - mildew buildup in the HVAC system. More common in damp/humid conditions.

If that is the issue, I wouldnt try to DIY it. There are professional tools companies can use to "fog" the HVAC system, sort of like bug bombing a house only on a much smaller scale.

[lalitv74]

Usually it's mold buildup because condensation from the A/C isn't able to drain adequately(sp?). You live in a very cool and wet climate, and to be honest I can't see how you would every drive the car w/out the A/C running. The smell will disappear after you've run the heat + A/C for awhile..

[current]

If the cabin air filter doesnt fix it, spooner touched on what the real problem could be - mildew buildup in the HVAC system. More common in damp/humid conditions.

If that is the issue, I wouldnt try to DIY it. There are professional tools companies can use to "fog" the HVAC system, sort of like bug bombing a house only on a much smaller scale.

I think I have to rely on professionals then.
Thanks for your advice.

[current]

Once the cabin filters are replaced it should go away

Hope so. Thanks.

[current]

Replacing the cabin air filter does not always remedy the problem. It's a common issue in e46's and is a result of mildew that builds up inside the ducts from moisture getting stuck inside while using the A/C. A few members have solved the problem by spraying a cleaner/disinfectant or something of the sorts in the exterior intake part of the vents. Remove the air filter turn the fans on high (with all your windows open) and spray vigorously.

There is a DIY on it I believe, google, e46 duct smell fix or something of the sort.

Have ordered some different products as foam and disinfectant spray. Thanks.

[current]

Usually it's mold buildup because condensation from the A/C isn't able to drain adequately(sp?). You live in a very cool and wet climate, and to be honest I can't see how you would every drive the car w/out the A/C running. The smell will disappear after you've run the heat + A/C for awhile..

Shall I use the heater and the AC at the same time.
Thanks

[ptarditi]

Running the a/c with the heat on helps to keep the windows defrosted. You also must make sure the drain for the a/c evaporator is not pinched or clogged, usually accessed from underneath the car. We use a system from Wynn's to disinfect the vent system. We also use a product called "frigi fresh" in mild cases. It also helps to keep the car smelling fresh as a daisy but limiting human methane output.

[current]

Running the a/c with the heat on helps to keep the windows defrosted. You also must make sure the drain for the a/c evaporator is not pinched or clogged, usually accessed from underneath the car. We use a system from Wynn's to disinfect the vent system. We also use a product called "frigi fresh" in mild cases. It also helps to keep the car smelling fresh as a daisy but limiting human methane output.

That Wynn's looks like the one from Wurth called Vapomat. $400 here in Norway.