AC odor removal and cleaning

[jgrgnt]

I just posted the following in another thread related to AC odor, so thought it might be useful/helpful to some to re-post it here...

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Here is some information that might help those of you who are still struggling with this odor/smell.

I too recently did the foam cleaning and cabin filter change myself. It definitely eliminated the smell. However, the smell I had prior to this service was not the moldy/musty smell that most everyone has been describing. My smell was more chemical in nature. Hard to describe exactly, but it was definitely noticeable. Thankfully, the smell only stuck around for the first 10 seconds or so after I initially turned on the cabin fan and/or AC. After that, the smell would completely dissipate/disappear. I took delivery of my vehicle almost 1 year ago (in early August 2019) and started noticing this chemical smell about 2 months ago.

When I called my local Tesla SC to order the OEM cabin filter, they thought it was a bit unusual to change the cabin filter so soon. So, I described the problem/smell to them. They looked up my VIN and quickly came back to inform me that Tesla has a newer/updated part for the HVAC system. It is called an "inner duct plenum" and is supposed to improve drainage in the HVAC system. I guess the "older" inner duct plenum design did not allow for complete/proper drainage of the condensate. So, this may be what is causing the smell to return for some or many Model 3 owners. My vehicle was built in July 2019. So, I do not know exactly when Tesla starting using this newer/updated "inner duct plenum" part in their production.

Attached is a copy of the Service Order from my local SC, which describes/shows the optional quote for the inner duct plenum (see line item #2). As you can see, the part itself is very inexpensive ($11) and labor to install is also inexpensive/reasonable at just $58. This can be done by Tesla mobile service. Therefore, I presume it would be a relatively easy DIY job for those who want to avoid the $58 labor charge.

I have decided to wait & see if my particular chemical smell returns. If it does return, then I'll probably either have Tesla change the inner duct plenum or buy the part and do it myself.

Hope this helps some and good luck!!

View attachment 561602

Good to know, thanks for sharing.

The part you referenced is #3 in this diagram. It appears to be on the frunk side of the firewall, so I wonder if its purpose is to drain water that collects in the intake tract, rather than condensation inside the HVAC assembly.

 

[israndy]

Had my computer updated to HW3 yesterday Anyone got HW3 retrofit yet?

Was lucky that the Mobile Tech allowed me to empty a can of coil cleaner into my ducts while he unhooked the computer in the frunk. He even pulled the filters for me. What a positive experience.

Hopefully, I won't have this issue again in two years what with the software update and the coils getting a good cleaning.

 

[crackers8199]

It should start about 10-15 minutes after parking the car.

that would explain why i didn't see it immediately. also, i may be stupid and the smell i was experiencing may have been remnants from whatever was on my hands and the hand sanitizer i used immediately upon entering the car and before removing my mask...today it hasn't come back after multiple drives.

 

[Aellinsar]

Thanks for the information on the plenum. I noticed the smell coming back the past couple days. It doesn't smell after being parked for a long time (i.e. in the morning when I get in), but if I come come leave it parked for 30 mintues then drive somewhere else I notice the smell.

We talk about the car being low maintenance, but if I have to change the filters and fog the A/C once or twice a year, that's pretty similar to having to do an oil change twice a year in cost/time.

 

[Turbojim]

That little bottle that Tesla uses is cheap stuff and not sufficient in my opinion. I used a kit from BG. BG sells professional grade chemicals to tons of car dealerships. If you’ve ever had flushes, or fuel induction services done on ice vehicles, there’s a good chance the dealership used BG products.

Anyways, since I work at a car dealership I bought an the a/c evap coil cleaning kit from the parts department. The big can is what you spray on the evap coil. The foam in the can will fill the entire cavity up a few times over. I filled the cavity up, reinstalled the cabin filter door, and ran the fan speed on 4 or 5 for about 5 minutes. I repeated this process twice until the foam was gone from the can. You will probably want to put a drain pan under the car because of the cleaning solution running from the evap drain. The little spray bottle you see treats the new cabin filters going in the car. It’s been almost a month since I treated our ‘19 SR+ with 16k miles and the smell has not come back.

 

[M109Rider]

That little bottle that Tesla uses is cheap stuff and not sufficient in my opinion. I used a kit from BG. BG sells professional grade chemicals to tons of car dealerships. If you’ve ever had flushes, or fuel induction services done on ice vehicles, there’s a good chance the dealership used BG products.

Anyways, since I work at a car dealership I bought an the a/c evap coil cleaning kit from the parts department. The big can is what you spray on the evap coil. The foam in the can will fill the entire cavity up a few times over. I filled the cavity up, reinstalled the cabin filter door, and ran the fan speed on 4 or 5 for about 5 minutes. I repeated this process twice until the foam was gone from the can. You will probably want to put a drain pan under the car because of the cleaning solution running from the evap drain. The little spray bottle you see treats the new cabin filters going in the car. It’s been almost a month since I treated our ‘19 SR+ with 16k miles and the smell has not come back. View attachment 562318

Can you elaborate on why the stuff Tesla uses is cheap an insufficient ?
Are the compositions in one different or better than the other, and why?
Thanks

 

[Turbojim]

Can you elaborate on why the stuff Tesla uses is cheap an insufficient ?
Are the compositions in one different or better than the other, and why?
Thanks

Being in the automotive business all of my life, I’ve never heard or seen this brand used in a professional setting. It may be the greatest stuff on earth, but the reviews and videos seem to give mixed results.

I’d rather go with a company that’s been around since the 70’s and all they do is make professional grade chemicals for professionals. I don’t work for them, nor have any affiliation. I’ve just been using their products for many years.

 

[Falcon3]

Anyone have this problem return this year? We are into summer now so ACs are running.

yes, it happened to me. My filtered was replace last year around the same time. I wonder if the filter needs to be replaced again or if there is a defect in the AC unit?

 

[marnao]

yes, it happened to me. My filtered was replace last year around the same time. I wonder if the filter needs to be replaced again or if there is a defect in the AC unit?

Read back a bit in this thread.. someone got a replacement part that may help. I scheduled service for next Friday and I asked for the same part to be replaced along with cleaning and changing the filters.

 

[israndy]

When I did mine the other day during my FSD computer update the Mobile Tech said that the cleaning spray that I was using is basically what they do when you bring the car in for this issue. I recommend buying new filters and the coil cleaner and then taking out the old filters, spraying the cleaner, waiting 20 minutes, and then installing the new filters. Probably spend less than $35.

 

[bigroo42]

Checking in to share my experience. had the car for 11 months and started to smell that funky smell when i started up the car after it had been sitting in the sun a few hours. yada yada yada. mobile tech comes out and charges 142 bucks and sprays "kool it" (i think) on the coils while changing the filters. i inquired about this being covered under warranty since it's happened so soon and, by his own admission, was the result of a firmware issue (i think that's what he said). he said nope - tesla was doing it as a courtesy during the first 6 months of ownership back in 19' but not any more. ah well...i thought i could watch him change the filters and do it myself the 2nd time, but after watching him, i'm not thinking it's something i want to tackle.

my question is this; (mobile tech answered no to this question) should i still be selecting "A/C off" when i select cabin overheat protection mode? i had read that this is the root of the issue. So, back in like October when i first read this, i switched to that setting. However i stilll got the smell.... so, i'm not sure if that helped at all or not. The tech claimed the "issue is fixed" with the firmware update a few months ago.

 

[Falcon3]

Read back a bit in this thread.. someone got a replacement part that may help. I scheduled service for next Friday and I asked for the same part to be replaced along with cleaning and changing the filters.

I read on another forum there's something called HVAC plenum that was replaced at some service centres for earlier model. My model falls in the earlier model b/c it was a May 2018 production and vin in the 20k. I'm going to contact service centre to inquire.

 

[israndy]

Let us know the results.

@bigroo42 I believe the firmware the Mobile Tech was talking about runs the fan after you leave the car w/o running the AC. My understanding is about 15 minutes of setting after you get out of the car, the fan is run to evaporate anything that remains in the plenum so no mold or mildew can form in there.

I also understand that the early cars did have a different design on the plenum, but that this software was going to be the fix, not replacing everyone's dash. As a Tesla investor, not just an owner, I appreciate them going for the easiest fixes as long as they are actual fixes. I have the same smell on 3 of my other cars, but those manufacturers are not going to cover them under warranty nor are they coming out with a software fix to prevent the issue in the future. Now that I know the Kool-It spray can fix I can take care of those cars myself.

 

[Az_Rael]

I wonder what the changes are on the new plenum. I would be up for paying for that change if they did improve the drainage.

 

[Az_Rael]

Using eBay, found pics of a revision C vs revision D. Couldn’t find an E for sale to compare, unfortunately.

 

[Lanzer]

Just dropping by to say that after a year, the smell from my AC did not return. *fingers crossed* Although I'm working at home now, so the AC did not work nearly as hard as last year. So I set a terrible example here.

Thinking back, I think I might had gotten water in the duct while washing my car. Would very much like to know if the new plenum does make a difference.

Always happy to see the community coming together to diagnose and contribute to solving various issues. Thank you for all who contributed to this thread!

PS - also had my HW3 installed, 2 months ago I had my windshield replaced, and the rep there said that she would call me if HW3 parts are in stock, and sure enough, I got a call 5 days later. Now I see more cones on my screen.

 

[israndy]

And trashcans

And those parts look identical. I was hoping there would be a drain in one that wasn't in the other or something.

 

[Az_Rael]

And trashcans

And those parts look identical. I was hoping there would be a drain in one that wasn't in the other or something.

yeah, the only difference I could see was the attach points. I was hoping the foam would change to closed cell vs what looks like open cell foam, but they look the same.

 

[Lanzer]

Just dropping by to say that after a year, the smell from my AC did not return. *fingers crossed* Although I'm working at home now, so the AC did not work nearly as hard as last year. So I set a terrible example here.

Thinking back, I think I might had gotten water in the duct while washing my car. Would very much like to know if the new plenum does make a difference.

Always happy to see the community coming together to diagnose and contribute to solving various issues. Thank you for all who contributed to this thread!

PS - also had my HW3 installed, 2 months ago I had my windshield replaced, and the rep there said that she would call me if HW3 parts are in stock, and sure enough, I got a call 5 days later. Now I see more cones on my screen.

 

[phigment]

I live in Canada, so don't run AC for most of the year. I got my model 3 in may 2018. First summer I had no smell. Summer of 2019 it stank once I started to use AC. Service cleaned it out and the smell didn't return.... until I started using AC again about a month ago.

It seems like this will be a yearly maintenance for me.