UGH - The smell of it. [AC Smell]

[dduffey]

Climate (weather) definitely has an affect. High humidity climates in particular. I believe also having the car sit in a mild temp are (garage) also contributes (verses leaving it parked outside to bake).

 

[bsf29]

I have had the mold smell issue with several ICE cars over the years due to the high humidity here in NC. l’ve learned to turn the AC off about 1/4 to 1/2 mile from my destination to make sure there is time for the condensation to clear out of the ducts. Tesla had an update last year(?) to keep the fan on longer after parking to help. Since I still do my manual process I’m not sure how much of an improvement it made. I’m also wondering if those that had the mold issue and tried the foam cleaning, really got all of the mold since some report the smell comes back.

 

[stopcrazypp]

I have had the mold smell issue with several ICE cars over the years due to the high humidity here in NC. l’ve learned to turn the AC off about 1/4 to 1/2 mile from my destination to make sure there is time for the condensation to clear out of the ducts. Tesla had an update last year(?) to keep the fan on longer after parking to help. Since I still do my manual process I’m not sure how much of an improvement it made. I’m also wondering if those that had the mold issue and tried the foam cleaning, really got all of the mold since some report the smell comes back.

Yeah, the last part is what I suspect is the issue with those that have it come back in weeks. The mold is still in the car somewhere, so just swapping the filter and doing the coil clean doesn't last very long as the mold smell just returns after the filter is saturated.

 

[driver7]

Would like to share my setup that seems to have eliminated the AC smell issue. I haven't had the smell return in over a year so sharing it now in case others would like to try it as well.

First some background. I live in VA with humid summers. The car is always parked in the garage overnight (the garage has no heating or cooling). The car AC settings are always on default, including re-circulation and cabin overheat protection. My M3 is from mid-2019. I first noticed the bad smell in the summer of 2020. Mobile service cleaned the coils and replaced the filters with another set of OEM filters ($140 charge). The smell went away but came back the following summer. So in 2021 I decided to perform coil cleaning and filter change myself. As has been documented multiple times, it's a cumbersome process, at least the first time. But I am glad I went away from Tesla doing it for me and have been enjoying a smell-free car for over a year now. Here is what I did:

• The following videos helped me to learn the filter swapping process: video 1, video 2, video 3. If you are even a little bit handy you can do it!
• The last video shows a magnetic cover ($30) that makes all subsequent filter changes a lot easier. I highly recommend you get it if you will be doing your own replacements.
• For cleaning of the coils (after taking out the old filters but before putting in the new filters) I used Klima AC cleaner ($18). I know others mentioned using 1-2 cans, but I used only 1/3 of the 10 oz can on each cleaning (in 2021 and 2022). If you install the magnetic cover, you can use the AC cleaner more frequently than only when swapping filters. I do it once in the spring and once in the fall (i.e. a can lasts me 18 months). After you've squirted the cleaner be sure to put back the cover before starting the drying fan
• After I am done blasting air to drain the cleaner, I then take a small mirror, shine a light onto it and angle the mirror towards the AC coil and drain pan. If I see any dirt or remaining cleaner I use a swiffer duster handle, wrap a few paper towels or wet wipes and wipe the remaining stuff from the drain pan.
• In 2021 I installed Taptes air filters ($38). The important part is not the brand, I believe, but the PVC frame of the filter. Unlike paper-framed OEM filters, these don't stay soaked when in contact (or close proximity) with the AC condensate. I believe this goes a long way in preventing any kind of growth (and subsequently smell) in the system. When I was cleaning the system last week the 1-year old filters looked clean so I put them back in for another year of service.
• Every 4 months I replace a pre-filter in the frunk ($19). Each time I also use a wet paper towel to clean the air intake area going as deep as I can reach (requires removing the plastic cover and frame on which the pre-filter rests).
• Annual cost maintenance is $88 ($6 x 2 AC cleaner applications, $19 x 3 for pre-filters, $38 / 2 for the PVC framed filters).

Hopefully this helps you remedy the smell issue in your M3.

 

[Romeo Alpha]

Was surprised Tesla only charged $70 plus tax for filter replacement and coil cleaning when they came out to the house on Monday. I expected $150ish.