davbargo

I drive a 2015 Lexus ES 300H that I bought used in May. About a month ago I started getting a bad smell in the cabin. The smell is hard to describe, but I initially thought it was either a dead animal or mold. The smell is usually worse after it rains, and it's present in the car before I turn it on. Searching on this forums I thought it could be one of three things:
1 . A dead animal in the A/C
2. Mold in the evaporator coil
3. Trapped water somewhere that is allowing mold build-up

I brought the car into the dealership for service and asked them to look into the smell. They said they used a boroscope to look for a dead animal, and couldn't find one. They changed the cabin air filter to a carbon filter. I asked them to do an A/C refresh with the toyota foam kit, but they said they dont do them anymore because the evaporator coil has an antimicrobial coating. I'm not sure if I buy into the coating preventing all A/C mold, but they said they couldnt find anything identifiably wrong with the A/C that would warrant foaming the evaporator. They weren't convinced the A/C is the culprit and they were worried a foam A/C cleaner kit could damage the coating. (Though they did admit to smelling a little "bad odor" on the old filter.

Then yesterday I opened up my trunk and opened the spare tire well - and the smell got much stronger. The well was dry, but there was flaky yellowish green stuff in the bottom of the well. The trunk itself (above the wheel) has always been dry anytime I've checked, but clearly there must have been some moisture or water in the spare tire well recently. I took some pictures. Based on this, I'm guessing water is building up there after it rains and causing mold or mildew growth. But I dont know enough about cars to know where to check for a blockage or leak . Is it possible the plastic shroud under the car is blocked, and water is coming up through the rubber gaskets? Is it more likely some other channel in the car is blocked and filling the well? To my knowldege, it seems the trunk area above the tire seems to stay dry. Please let me know the best route to figuring out how to find and fix the issue. And lastly, do you think it's a safe assumption that this is the cause of the smell, or do you think there is still some reason to suspect the A/C?


Spare Tire Well

Closer view


The mat in the trunk is always dry, so I dont think any water has reached it.

Some blockage here - could this be related?

kxaz145

This looks like high water damage to me.

davbargo

Thanks for the input. I had a mechanic inspect the car before purchase, and there was no sign of water damage then. Granted, it could have happened after I bought it. The last time I opened up the spare tire well, I didnt see the flakey green stuff - that's new. While it's been in my possession, it's never been anywhere near a flood or deep water. Can the water be backing up from a clog somewhere or leaking in after rain?

lesz

I would be curious about the title history of the car and, specifically, about whether it was ever in use in an area that experienced widespread flooding. I recall reading an article, at the time after the hurricane-related flooding in Houston, about unscrupulous people taking flood damaged cars to the north and selling them to unsuspecting buyers.

davbargo

The title is clean, and the Carfax and Lexus service history showed the vehicle was used in New Jersey only. Also, Lexus certified it, and I doubt they would do that for a flood damaged car. Also, let me expand on info I put in my post: A few weeks ago, I pulled out the spare tire to see if the smell might be coming from the well. The well was dry and there was no flakey green stuff, and I didn't see the white water-border that is visible now. But I did notice that the rubber tape-looking stuff was moist in a few spots. The pictures I posted are of the car yesterday. There hasnt been any flooding that the car has driven through since the first time I checked (or anytime I've owned it), but it has been parked on the street while we had on and off rain - Which makes me strongly suspect that water is getting in somehow while it's raining.

The smell gets worse / strongest every time it rains... and seems to get milder when its hot for a few days. I appreciate all the replies, but does anyone have any insights or answers that aren't related to "prior flood damage" as a possible cause of the smell?

john341

Any chance may have spilled milk? You can take those three Black Gourmet out and use some Clorox as cleaning agent and hose the spare well down, without getting water anywhere near 12 volt and hybrid battery.

Also, just a thought; degraded Pressure vents on the side of the rear bumper may cause water to get in.

pab12

Could the sun roof drain lines be blocked leading to a path for water to drain into the trunk?
I'm not familiar with the drain routing for this car, but on my jaguar the drain lines from the rear of the sun roof, come down behind the rear door and exit out the side of the trunk under the trunk lining. Any blockage allow the water to drain down into the trunk itself.
Good luck.
=================================
My karma just ran over your dogma
Current Hers: '13 Lexus ES350
Current Mine: '15 Jaguar XF (its aubergine)

john341

I Was also going to Suggest about the drain tube. its usually translucent pink tube for the rear drain and white for the front(could be vice versa) about 1/4 inch in diameter. It could be clogged since the pictures show lots of leaves on the car.

sshowell99

I own a 2014 ES350 with 60k and I have the same problem, after a hard acceleration I smell what I can only describe as "rotten eggs". This only happens after get on it hard and then resume speed. Odor dissipates and smell goes away. Somethings wrong and I think Lexus needs to address this and let us know what's going on, this is not the first posting of this nature and won't be the last. One other detail, when I switch from cabin air to outside air it seems I don't get the smell "STRANGE"

gamma742

That sounds like a bad Catalytic Converter.

Mike728

^^Yes, Sounds like the converter is plugged up. Not at all related to the OP's issue, from what I can tell.

davbargo

Thanks Pab12 and John341. It sounds like either of those possibilities (blocked sun roof drain lines or degraded pressure vents) could be it. What's the best way to figure out if these are the issue? Do I hose down the car and see if water leaks somewhere? Or should I be looking for a service manual or youtube video on how to find and clean the sunroof drain tubes?

jamestpc

I had a buick enclave as my last car...same kind of description - it wasn't a bad smell, but musty.

Sometimes i'd find the rear floors wet too.

I checked the trunk but I actually found water in the well. Turns out there was a sunroof drain tube running down the left side of the trunk...I have no idea why but there was a push connector to extend the tube down and out. It had disconnected itself, so was draining into the trunk.

I fixed it and never came back. But the water was in the foam, so it likely moulded over the months I couldn't figure it out.

I dont' have that car anymore.


Pull the side paneling in the trunk to see if there's any drain tubes running there. Once you have the trunk bare, run a hose over the roof of your car to see if any water is making its way into the trunk.

pab12

>What's the best way to figure out if these are the issue?
Sorry, if no one on this list has investigated this issue then it seems like you might be the first...
But since you just had the car at the dealer for this issue I might suggest calling them and asking if they checked for blocked drains and if not why not? It seems like this could be a common problem that they should have routinely checked, and if they did, then you would like to know that.
Otherwise start investigating (I just googled "lexus es 350 sunroof drain" and got lots of hits).
Good luck
=================================
My karma just ran over your dogma
Current Hers: '13 Lexus ES350
Current Mine: '15 Jaguar XF (its aubergine)

danfrphils

Hi OP, having same issue with my 2014 Lexus ES300h. Discovered foul smell. After a week of searching, found about a quarter inch of dark, dirty water at the bottom of the wheel well. After drying everything up, I discovered small bits of water at same place after about a week of raining this week. Did OP figure out what the source of the problem is? My spare tire well picture looks almost exactly like OP's.