This design flaw makes Tesla’s Model 3 smell bad (PART 2) 

Why don’t you use duct tape to cover all of the bottom of the filter

The amount of effort behind these series is insane.

I am beyond impressed with the effort you took to investigate this issue. Getting the module itself was truly a "hold my beer" moment. 😂 I hope this amount helps towards your costs to get this video made.

I usually don’t comment on videos, but I’m here just to say “Well Done”. Efforts you are putting for this series is astonishing.

When you unwrapped that module, it was an instant like from me. 🤣

I hope this video gets a ton of views. The amount of effort put into it is certainly recognized.

These two videos have been awesome, thanks for putting in the effort and sensibly approaching and addressing the problem!

You’re really incredible ! Never seen such attention to detail, curiosity, and never giving up to find the solution ! Love it

I dont even have a Tesla, but I found your first video interesting. My jaw dropped when you unboxed the HVAC module to help you figure out the problem. If you keep this kind of content quality up, youll be a full time youtuber next year...

I love the logical thought process and thorough testing methodology. As an engineer this video was a delight to watch.

I just did the gasket install with new filters a couple weeks ago. This video was bittersweet for me as I thought I solved the issue and now I see I should probably change to those other filters that don’t absorb the water. Haha. Seriously though, the dedication to this issue from you is remarkable. Can’t thank you enough for putting in this effort to solve one of the most nagging problems with these cars.

This videos series should be used as a tool for anyone considering to study engineering. If you like this video, you’ll love engineering. Great job!

Tesla should pay this man as a quality control consultant and troubleshooter.

I’ve had my 2018 Model 3 for over 5 years now, and I live in Phoenix, AZ. I got the funk smell in my car with the OEM filters, but I’ve been using “HEPA” replacement filters with the open cell foam around them for about the last 4 years. I haven’t had the funk smell since I started using them. The reduced airflow has not been noticeable to me, and as you can imagine, it gets very hot here in the summer (the A/C still works fine). I think your hypothesis about the open cell foam not retaining moisture at the bottom of the filter is valid based on my experience.

I run a local EV repair shop where we run odor removal services for Model 3/ Model Y, this series is INCREDIBLY informative! Thank you!

I am one of the desert dwellers with odor problems. I’d love to add some data to your findings. I live in Boise Idaho where the summers get to triple digits and winters can hit single digits. I only ever have odor issues in the summer. The “fix” I have implemented is in the early summer when the smell starts I buy new filters and buy the condenser cleaner and do a full clean out before putting new filters in. I tried just replacing the filters. And that worked, but the smell came back within weeks. If I do the full clean, let everything dry, then put in new filters the smell stays gone for most if not all of the rest of the summer. I’ve been doing this since 2019 with 3 different Model 3s and one Model Y. As soon as cooler weather hits and the AC isn’t being used the smell goes away. The smell is the worst when getting in the car on a hot day and starting the AC. After the AC runs for 5 mins the smell is mostly gone. But it’s really bad for those first few mins. I really feel like the AC and the resultant water condensation is the problem for me. In the summer after running the AC really hard there will be a puddle under the car if it sits parked for a while. I imagine that puddle is most of the condensation, but that some of it wasn’t able to escape the car and is causing the odor. Tesla didn’t used to run the fan to try to dry anything out and I still had the problem back then. It’s gotten a little better after they started running the fan to the to dry things out. Only a little. I really hope you keep digging into where the odor is coming from for different people in different places.

Kudos for this guy. Buy an entire assembly to solve an engineering mystery 😅

Adam, you need to be hired by Sandy as he deconstructs Tesla vehicles for their brilliant designs and occasional flaws. Great job on your part! Loved the resolve to find the problem.

If that little orange plastic piece is 3d printed then it could be worth including a slot for a magnet to be installed inside it, that way it would be easier to fish out using a magnetized pole (like the ones they use to get keys out of drains).

You should get a job offer from Tesla for this effort!

First time I've ever donated to a channel. Amazing effort and impressive skills to get to root cause. Thank you!

Bro it’s a crime this channel isn’t at 100k subs. Thank you for the dedication and putting this much effort into this issue.

Wow!!!!!! You win when it comes to this issue. Much respect for the time and persistence you gave to this problem.

I'm going to use "open cell foam frame" filter on the bottom and a regular one on the top. Problem sovled!

Regarding the aftermarket frunk gasket, you can install the gasket only on the passenger side, so water closest to the intake vent will get blocked off, while air from the driver side can still freely feed into the cavity. Might be worth measuring to see if it’s worth trying

This is really fine work! Tesla ought to be ashamed! I am a scale modeler and extensively use acrylic medium. It’s water based and easily absorbed by paper. When it dries, it’s moisture proof and has a hardshell finish. I’m thinking you could paint the filter bottom with the stuff and after it dries, a few hours later, it’s moisture-proofed the part of the filter you applied it to. Thanks for a great video!

The amount of work put into this video is impressive. Thank you for being so thorough! For me so far, your first solution is still holding up and working well. I look forward to more videos from you!

Give this guy 10k subs for going above and beyond! Kudos to you! Shared!

I installed aftermarket cabin filters almost exactly a year ago that have the foam lining around the outside and I can say with certainty that the bad smells are gone. Usually about a month into a rainy season it would come back but nothing so far. My Model 3 is 6 years old and I’ve changed the filters with OEM ones 4-5 times. Each time the smell would come back in months. Here we are a year later and nothing! Great videos and kudos for all the experimenting.

Amazing attention to detail Adam! Thanks for your incredible dedication to rooting out and solving(?) this stinky issue. Heading downstairs to fire up my 3D printer and make one of these clips.

Thank you so much for digging into this! I've been studying this problem for months and was just about to do a similar teardown-style investigation. Your work confirmed what I had already figured out through prior tests and observations. 1) It was primarily the filter that stank, not the evaporator. 2) Rain water was somehow getting into the filter. 3) Humid days would also trigger the problem. Our car is in a fairly airtight garage so Tesla's "solution" would suck that trapped, humid air into the filter and the car would smell horrible a few hours after driving it. FYI, I did try the XTechnor filter and while it did seem to last longer (6mo instead of 3mo) it would still get smelly, presumably because of organic matter inside the filter rotting, as you said in the first video. So that is not a complete solution but I think if it is combined with the gasket or removing the duct, would solve the issue. Your work saved me a lot of time so here is my thanks. I am printing that clip now and ordering a gasket. Might try a few other things, too. 😄

Im so glad someone has taken the initiative to start working this problem, would love to see a full resolution with prescriptive fixes based on geographic locations

I also live in New York and appreciate how much work you put into finding the cause of the funky smell. I always seem to notice the smell more in the warmer weather when running the air conditioner to cool the car.

I live in Reno Nevada and I have used the open cell foam filters since the first time I swapped the filters. I still get the funk smell even with those filters, so I am going to try removing the initial duct and adding the sealing gasket as found in your first video. But, to confirm, just using the cell foam filters is not enough on its own.

Appreciate all the work you’ve put into this series. I ordered some replacement filters a while ago and that did the trick for me. The musty smell on the old Filters is really awful

The effort put into this series is incredible. Well done.

I installed the gasket after your earlier video (and also did a filter change and cleaned the condenser) hoping it would solve the problem. As this video shows, it unfortunately did not. I live in SoCal and it's generally not super wet around here, however we do get a lot of cool, humid days in the winter since I'm close to the ocean. The smell came back as soon as that weather started happening. I think your theory that one of the causes of the mold and musty odor is, ironically, Tesla's software attempting to dry the system out. Hopefully they can change that drying cycle process to correct the problem. It's crazy that this issue has gone unresolved for so long.

You are my hero 🫡 This level of nerdery and dedication is what I'm here for. Thanks for making this series. So much to learn!

This is amazing. Thank you for all the time, effort, and money, you have put into this. The amount of work necessary to remove that one filter cover screw alone is a Herculean feat.

Man I was soo excited for the water to come up through the drain at 9:10

18:40: Open cell foam is more absorbing moisture than closed cell foam. But thanks for this ultra well analyzed problematic!

I work for company that makes the car heat exchangers. One of the exchangers - the evaporator core important to design this part where water can drain fully otherwise if stays moist then microbes buildup and produce smell with time. Also some of the evaporators are dipped in solution having chemicals with some zinc compounds that leave thin coating and prevents biofilm or microbe buildup even with moisture. This is extra cost and not all companies getting evaporators want to pay extra for the coating.

I am in central NJ and I have a 2021 Model 3. The cabin funk happened after about a year or so. I replaced my OEM filters with charcoal ones I got from Abstract Ocean. I kinda forgot about it since. Every now and again I get a waft of funk but it seems only when it’s been very humid/rainy out and usually when I am using the windshield defogger. Not sure if that adds a wrinkle or not. Thanks for your videos. Dedication to detail and the efforts you extend to prove your point are pretty impressive.

great findings... I'm just going to keep changing the filters every few months but it's nice to see why this might be happening

Adam, I just want to say thank you for the amount of time and effort you've clearly put into these videos. I bought the gasket and was hesitant to install it, worried about airflow. I think I'll proceed. Much appreciated.

From CNY to you in WNY, thanks for your informative & well studied video

I really enjoyed your efforts to identify this problem and was impressed with the levels you went to. I hope Tesla watches them. I have a 2022 M3LR and live in the Dallas TX area. I don't drive a lot and garage my car. When I first got my car, I enabled recirculate like I always did with ICE cars. There were a few times when I got in to drive when there was a musty smell. I turned off recirculate and haven't used it since and have had no further smell issues. This effort was absolutely trivial in comparison to yours. A factor could also be use case. Mine is mostly short local trips, no commuting. Others may commute to work, with their cars parked outside and then return home which would be very different. In any case, your videos were enjoyable and very educational. Thank you!

Great job!!!! I think getting the xtechnor filter seems like the best solution. I’ve already got the aftermarket gasket installed.

Very good video with tons of work behind doing all these testings, bravo and thank you to you

this is dedication! I have a 18 Model 3 with on again / off again stank and I definitely plan to utilize your tips! Seems like it mostly comes down to keeping that bottom filter edge from getting wet. Easy enough to try next time I'm in there

Thank you Adam! I'm about to change my cabin filters again and saw this! I'm only 11 minutes in! Awesome content!

This was superb investigation. I very rarely comment on RU-vid videos and I wanted to say thank you for the effort and thorough investigation and testing you put in to this. Looking forward to whatever comes next! Love the unboxing grin at 10:49 😂

The most thorough tesla tests I've ever seen. The effort in this video is astounding. Thank you so much for doing all of this hard work for free for us all. I hope your channel explodes.

Your level of detail and effort is incredible. Rarely I see RU-vidrs at this level. Tesla engineering seriously needs to take notes. Everyone please try to send Tesla with links to this video, they must address this.

This video is fantastic! I absolutely love that you bought a whole hvac assembly! One quick note is that the style of fan used in these systems can't move the air in reverse. If the fan runs backwards, the airflow direction is the same, however it is much less efficient at moving air.

Hi, thank you for spending time and making the videos. It would take a lot of your time, installing, uninstalling, then even bought a whole a/c duct system. I think mold and bad stuff grow in the second compartment of the draining pan, (not the compartment that the filter seats on, the other one).

I love your dedication man. Just yesterday, finally had a chance to put in the solution you landed on in the last video. This makes me convinced that it will at least help a little!

You went above and beyond. Thank you so much! I'm going to make some changes to my car.

Fantastic video! Love that you explain everything in such a great detail! With this kind of quality you should become the next big youtuber!

Absolutely Amazing! The level of detail AND you even bought a complete HVAC unit! I don't own a Tesla but thoroughly enjoyed watching the process.

Interesting you have a stink it the winter, I live in Sacramento and we sit around 90% humidity in the winter, but I only have the smell in the summer

Here in Southern California our air is very dry and very hot in the summer, and when the AC is running the entire evaporator in our house gets completely soaked with water when our heat pump is running in our house. To the point where it fills with water. It's the reverse in winter when the heat pump is heating, water pours out of the outside evaporator our air in winter is also quite dry most of the time. It's the same in the Tesla -- somehow what little humidity there is in the air is pulled out of our air at 10-50% humidity. You'll see *puddles* of water underneath every tesla at the superchargers haha, little rivers flowing out from each one. My filters are definitely wet, I can see evidence of that by the water marks on the bottom filter.

Thank you for your effort to sort that problem out!!!.

Thank you! I'll be pursuing the 2x filter solution (Xtechnor on bottom and Wix on top) + the hood shroud to prevent ingres from the outside. The auto dry sequence being a problem is an excellent find!

Awesome. Can't believe the great view of the entire interior unit you had. Thank you.

What an exhaustive and comprehensive tests you've done, I really applaud the thought and effort that went into this! Even a whole HVAC units under the dash! I had a theory as to why it was getting wet, which is the evaporator fins might be too cold after shutdown and starts to condensate from ambient area. The moisture somehow gets onto the filter or just the fact that it was high humidity in a small area was enough to "wet" the filter? But then Tesla's own bandaid fix of running the HVAC pulling in fresh air should have dried it up? I'm just theorizing.

I can't find the post now but someone on Reddit mentioned they have a 2018 and they 3d printed the bracket and had trouble fitting the filter back inside the car. He thought the bracket was too wide and risked popping off when trying to squeeze it through the opening. They weren't sure if "older" Model 3s have a slightly smaller filter access door.

Thanks for the finding & your deep dive analysis. My 2019 LR M3 was getting this issue in late 2020, however issue was resolved after replacing the air filter & never has that issue again ever since. For the idea of printing a clip, I think it will work the same if you place a piece of duct tape or aluminum duct tape on the bottom of the filter and cover 1/2” up, the glue will hold it . Thanks for the clip as it the first time I could see the whole ducting system of a M3

Your dedication is unmatched. Thank you!!

Thank you for your videos. I got the frunk gasket assembly after watching your first video. It just makes sense that the water coming in would be the problem. I believe that it has helped. I haven't noticed the stink since. Seems strange that a company like Tesla wouldn't have done a better job of testing this. Great video.

Thank you for making these videos. So educational!

Truly appreciate your video. The quality of work is phenomenal.

Thank you so much for doing this. This series has been very helpful!!!!

Adam, we all appreciate ALL you do! Are you ever going to investigate potential solutions for the road noise issue?

Great experimentation. Hotwire anemometers are consistent in laminar airflow through a channel and perpendicular mid-channel tip position. Turbulence in a channel may lead to frequent changes in results, especially for higher quality anemometers (faster response for more refined data). A vane anemometer can provide more consistent readings in turbulent flows, partly due to blade momentum. Moisture condensing only above the drain hole might be due to adiabatic expansion on the downgradient side of the drain, cooling the filter frame and material in that vicinity which increases probability of condensation. Maybe plug the drain, or anything to block that opening to support your theory.

Wow, exhaustive! Thank you for all your ingenuity and time.

Now this is some next level research. Amazing work - love the dedication, including the effort put to film and show us your measurments. Absolutely brilliant!

These videos have a lot of interesting information. Thank you for going through the trouble and expense to try to figure it out. I have a strange variation. I bought my Model 3 in 2019 when I lived in the desert. The smell would come and go intermittently, sometimes within the same drive. It could get so bad that I would drive with the windows down on a 115° summer day. Changing filters and using foaming evaporator cleaners would only last weeks. The car was garaged there. I moved to northern New Jersey in November 2022. I now have an apartment without a garage and haven’t had the smell since.

These are some really comprehensive high effort videos. Great work.

Thank you so much for this series. The Tesla HVAC funk is the only ongoing issue I have with my cars and I love learning more about what might be causing it.

Nice work in helping to figure this out, Adam. It seems like the air movement past the drain hole is creating a vacuum that pulls any stagnant water (or even just humidity in the air, because I bet that material on the edge of the filter holds moisture easily) back up the drain. That would certainly explain why the 3d printed clip is making a difference.

I implemented some of the recommendations from your first video. The second video is stellar, and I look forward to part three.

Very nice diving deep on this! I think that moisture might still be accumulating there as a result from water not completely draining from the pan and normally evaporating, finding its way through the small duct in the filter pan (and the drying cycle accelerates that). If that duct was blocked, very likely the vapors would spread out on the filter instead of accumulating in that area. If you dig a bit deeper youll find other cars with this issue, the c-class MB had a class action lawsuit over this as water dles not fully drain out from a design issue and causes the filters to moist and smell bad when parked (i had one with this issue and decided to sell the car).

Great video. You keep getting closer. Hope you figure it out in video 3.

Project Farm of Tesla issues. Love these videos. Please keep coming.. Subscribed to your channel. Hope it grows immensely.

This video was so awesome. Such quality that I didn’t even want to skip ahead! Thank you very much for taking the time to do this I’ve learned a lot.

Incredible amount of effort. The entire process is through and explained so well. Bravo sir and keep up the great work, please! 👍👍👍

Was watching your video and the first thing this reminded me was the cabin air funk / mildew smell with my 1993 Lexus SC400. I lived in Florida at the time, every few months I had to bring the car into Lexus and they sprayed a disinfectant into the AC system. Changing filters never fixed the smell. Anyway great video, and fantastic creative idea to 3D print a possible solution to keep the cabin filter from getting wet from the drain hole.

Wow! The “funk” has been driving me crazy. I suspected the source is the filters and your research and videos have confirmed it. It’s amazing Tesla hasn’t addressed this yet. THANK YOU!

Amazing effort! Subscribed right away. Thank you!

What a great video. You answered questions I didn't know I had!!

What an amazing video. It is so detailed and with great scientific backing given you are just one guy. Thank you for this!

The part 2 I never knew I needed!! Great video just like the first!

Great videos on this issue. I feel like you’ve put way more into solving this than Tesla Engineering has.

Big respect for going through this process. Thank you for being tenaciously curious!

thank you for your science and hard work!!! I'm getting delivered my seal and foam filters tomorrow, I can't wait!

Open-cell foam is far more water absorbent. You want closed-cell foam to prevent moisture from being collected.

Maybe , run the model3 without those filters for a day or two but measure the moister at the base area before and after and check a sniff test in this location for mold ordour as well.

I wish you had walked through the air flow path of the AC system you purchased. I used to be a HVAC engineer for Mitsubishi and remember many days sending cars through the water ingress booth with cameras in the intake system. Basically you always suck in water into the HVAC system when the duct size is small. The trick is to slow the airflow down to allow the droplets to fall out of suspension usually in a large cross area. The cars I worked on had a large box post fan with an oversized outlet to stop mud wasps laying larvae in the outlet. The filter was at the top of this box. My BMW does the same thing but with a large cross section filter before the fan below the air intake. I think the main problem with the Tesla design is it never slows the air down before the filter. This will always be a problem. Secondly the filter is very close to the evaporator which is very cold any like to pull heat from the filter causing it to limit post operation evaporation. Final thought is that there could be capillary action of condensed water migrating from the evaporator to the filter. This could explain the moisture profile and the benefit you noted from adding the clip. You could just paint the lower edge of the filter in a rubberised bathroom water proofing paint to confirm the capillary action.

Great video and going WAY past effort put in. Truly amazed me how much work you've put in. Your question about why moisture collects at the drain on the lower filter. I believe it's from the temperature difference with the air flow. That is the only access and the air temp moving between the lower (warmer area) and the upper outer(colder area) the water is condensing (might have that backwards). Growing up in the desert the misconception is low humidity = no humidity. To survive and collect water in the desert, you can put out rocks over a plastic bag to have morning dew/humidity condense and provide drinking water. As the bottom of the rock stays very cold, the top gets direct sun and heats rapidly. This creates an effect to change humidity into drinking water. I think you are looking at a micro environment creating this same effect in that filter area. To test this I think, you would need to put a temperature gauge in both areas to measure how large of a difference on both sides and how rapidly they change of temp of the bottom of the filter is. I'm guessing the filter over the vent gets extremely cold compared to one or both sides. Any evaporation or humidity is creating the dew that is being wicked back into the filter right at the temp difference. Software would need some kind of moisture or temp sensor in that area to modulate that depending on conditions. Guessing not worth it for Tesla to do that. Have the plate the filter is sitting on go across that opening, allowing the moisture to collect on it instead of the filter should fix that. An easy mod for Tesla if they are still using that setup in any new cars. Filter manufactures are probably the best solution at this point with changing the filter to have a water resistant bottom as you suggested. 3d printing a part would probably be next, as you stated someone selling that as an option for people that don't have a 3d printer themselves. Thanks again and hope this helps.