Bad AC Smell

[Alieti]

Hi everyone,

had the Y for about 3 months now. Last week when you turn the car on the AC smell is very bad, like sour or mold. It goes away after a few minutes but definitely not pleasant. Anyone else have this issue?

 

[HelixSpiral]

This has been a common issue with the Model 3. Some people report you can get ride of it by running the heat on HI and max fan for about 20 minutes. Others have said they had to take it to service to get the system cleaned. But it just comes back eventually.

Apparently the design of the 3/Y HVAC leaves too much moisture inside the system so it gets mildew. A software update sometime last year causes the system to run the fan only about 20 minutes after you finish a drive in order to help dry it out, but I haven't noticed it making a difference.

 

[Valore]

It's condensation water on the evaporator dripping into your a/c.
Like on a cola bottle you take out of the fridge.
Mold and bacteria form and start to smell.

Yeah, running on high temp / max fan helps a bit, but it's a design flaw that too much moisture builds in the system and doesn't get transported out.

 

[Dennisis]

This isn't an issue particular to the MY or Tesla - many cars get this at times, "Luxury" or not.

 

[Chaverim]

At what point does this warrant a recall/retrofit? A system designed in a way to grow mold is a major health issue.

 

[secondclaw]

Umm, if this is really the case, it may finally end my Tesla reservation. I live by the beach in extremely hot and humid climate, where mold is a constant problem. My 12 year old SUV gets occasional mold so filter has to be replaced, but it's like 2-3 years per replacement for me. I can handle $150 every few years but if this is a problem occurring every few months, this is not going to work.

 

[Chaverim]

Most cabin filters are check or replace every 2 years.

 

[Pied]

Do you see a water puddle under your car after using AC? If not, the drain line might be clogged. 3 months seems a little too soon for the smell to start showing up. It took a year in my Mazda3 for the smell to show up. My Model 3 has no smell at almost 2 years.

If the line isn't clogged, you can use kool-it and spray where the filters go.

 

[Matsayz]

Umm, if this is really the case, it may finally end my Tesla reservation. I live by the beach in extremely hot and humid climate, where mold is a constant problem. My 12 year old SUV gets occasional mold so filter has to be replaced, but it's like 2-3 years per replacement for me. I can handle $150 every few years but if this is a problem occurring every few months, this is not going to work.

It's not an every month thing. Most manufacturers will recommend changing the in cabin air filter every year, the Tesla Model 3 & Y require two of those which I think I paid $17 for on Amazon or something. As a couple people mentioned, Tesla supposedly put some code in an update last year to run the fan after the car is unoccupied after driving to dry the HVAC out... I haven't seen this happen but whatever. The smell comes and goes depending on weather and usage as you know living in Florida.

I wouldn't let this be the hill you say "I'm cancelling my car" on. There are other bigger hills to say no thank you when it comes to Tesla ownership. Wait until you see the panel gaps and lack of QC when it comes to the Model Y. Our was in a bit of rough shape but most everything has been fixed. I'm not saying let Tesla off the hook for things, not at all, they MUST fix these production issues or else the masses will not convert. The soccer mom is not going to put up with the HVAC not working randomly or the hatch not keeping it's preset opening level and smacking into the garage door.

If you were cool with $150 every few years then you'll be good to go with this car. You'll be saving $150 a year easily without oil changes and all the other required items of a gas car.

 

[secondclaw]

It's not an every month thing. Most manufacturers will recommend changing the in cabin air filter every year, the Tesla Model 3 & Y require two of those which I think I paid $17 for on Amazon or something. As a couple people mentioned, Tesla supposedly put some code in an update last year to run the fan after the car is unoccupied after driving to dry the HVAC out... I haven't seen this happen but whatever. The smell comes and goes depending on weather and usage as you know living in Florida.

I wouldn't let this be the hill you say "I'm cancelling my car" on. There are other bigger hills to say no thank you when it comes to Tesla ownership. Wait until you see the panel gaps and lack of QC when it comes to the Model Y. Our was in a bit of rough shape but most everything has been fixed. I'm not saying let Tesla off the hook for things, not at all, they MUST fix these production issues or else the masses will not convert. The soccer mom is not going to put up with the HVAC not working randomly or the hatch not keeping it's preset opening level and smacking into the garage door.

If you were cool with $150 every few years then you'll be good to go with this car. You'll be saving $150 a year easily without oil changes and all the other required items of a gas car.

Every few years is not a problem at all. The reports of every 3 months is what I have an issue with.

 

[Matsayz]

Every few years is not a problem at all. The reports of every 3 months is what I have an issue with.

I haven’t seen reports of every few months. My year old Model 3 only just started this but I’m in Vegas and run the A/C constantly. Again, this probably won’t be your biggest issue with the car when you get it and this is possibly one of the simplest fixes

 

[LasVegas2019]

No problem here in hot, humid Florida.

 

[rxlawdude]

I think Tesla improved the HVAC air intake on the MY. Our early M3 basically has a giant hole into which leaves and other debris can fall, which combined with condensate creates mold. The MY seems to have a plastic mesh over the intake.

 

[Matsayz]

I think Tesla improved the HVAC air intake on the MY. Our early M3 basically has a giant hole into which leaves and other debris can fall, which combined with condensate creates mold. The MY seems to have a plastic mesh over the intake.

I bought this intake grille for my Model 3, both cars have the metal grilled at some point in the cabin air intake, the Model 3 (at least June 2019 builds) the grille is waaaay down there. I think our Model Y is closer to the top but I’ll be buying a Model Y version of this as well at some point.


ROOCS Model 3 Air Intake Grille, ABS Plastic Air Vent Intake Air Flow Vent Protection Cover Inlet Cover for Tesla Model 3 Accessories https://www.amazon.com/dp/B07VD3TKLK/ref=cm_sw_r_cp_api_i_zxKaFbHBC8VHV

 

[Fobia]

No problem here in hot, humid Florida.

Lucky you. I have this issue. Does your car sleep outside?

 

[Lozzy]

In other cars I’ve had with this problem it’s from recirculating the air too much instead of having fresh air come in, which builds up moisture. Like others said running the heat or turning the recirculate off should solve it.

 

[LasVegas2019]

Lucky you. I have this issue. Does your car sleep outside?

No, Mine is garaged when not driving.

 

[LasVegas2019]

In other cars I’ve had with this problem it’s from recirculating the air too much instead of having fresh air come in, which builds up moisture. Like others said running the heat or turning the recirculate off should solve it.

I have been lucky. I have probably owned 30 cars in my life and only one had this problem which was my 2018 Chevy Colorado. It would smell like raw fuel from time to time.

 

[user212_nr]

I've just noticed this problem after a few cold weeks, now running the A/C just slightly mid-day produces a slight smell.

 

[mangrove79]

My Y had this issue a few weeks after delivery, at the beginning of summer '21. I was a new owner at the time and didn't have the luxury of knowing about these posts in TMC. As OP mentioned, the problem always goes away after a few minutes of full blast so it wasn't as annoying as could've been. I lived with it for the summer, and then the dry FL winter made the issue go away. That, was just a temporary reprieve as the smell has returned along with summer and humidity.

I scheduled a service appointment for it and was promptly given a cost estimate of $144 ($140 for the cabin filter replacement and the rest tax). I know some folks got their filters replaced at no cost (probably in the Model 3 threads), but I doubt I'll have similar luck. Will know either way tomorrow when mobile service gets here.