Inside smells really bad

I bought one from Wallyworld for like $45 for a different project that worked great. I believe the brand was pro breeze? It's literally the smallest one they sell in store.

When I do my filter service I like to treat the system with a short spray of Ozium into the cabin filter slot with the fan on high before I put the new filter in. I'll let it run for 5 minutes after with the windows down just to air it out a bit. I think this is the same stuff as the small can included with the Toyota kit. My other Toyota sits longer and tends to get funky faster, but I have gotten the wet dog smell in the Prius once or twice before. Carbon cabin filters are cheap, replace them often. I do them every 5k.

 

I have an ozone generator that works quite well for removing odors from a room.

 

I've change the cabin filter on our '10, once.

That said, I'm "somewhere", west coast Canada, maybe a lot less dust in the air.

 

We get a lot of pollen in the Pacific NW. I'm always surprised at how dirty my cabin air filter gets. Conversely, I was surprised at how clean my engine air filter was after the horrible forest fires in 2020, when we had the worst air quality in the world where I lived, for 10 days.

 

Remember this one?
I think Jerry drove a BMW in this episode.

 

Crystal cat litter can be used instead of Damprid. You need to supply a container, but an old sock will do. It can be regenerated in a 200F to 250F oven for an hour.

 

I spoke too soon.

During a cleaning I pulled up the rear all weather mats and noticed that under them they had speckles of condensation on the bottom of the mats. Weird because my back seat doesn't get used except for groceries and nothing spills in my car EVER.

The REAR PASSENGER SIDE FOOT AREA where it meets the plastic housing for the HV battery had a visible amount of moisture.

This moisture was not just on the carpet but had wicked up the plastic a bit as you can see in the picture.

This was noticed on the 2nd. I cleaned it up and have been checking it since. Visible moisture has not been present since then BUT squeezing my fingers between the carpet and the HV battery housing you see in the picture results in wet fingers (heh). So there is moisture collecting under there, source unknown.

My first assumption was the shark fin on the roof. I pressurized the cabin, air on high with external intake selected, you can feel with the door cracked that it's pushing air out the door. I shut the door and took a bottle of water + dish soap and sprayed around the shark fin. No bubbles. Rinsed and repeat to be sure, still no bubbles. So with that I don't believe the point of ingress is the shark fin.

I also took a borescope and tried to see if I could maneuver it to see anything useful. I think I saw some rust but can't be sure. My next step will be to remove the back seat cushion and visually inspect.

What I ask of you, if you have the wet dog smell, is to check the same area for moisture in your car during or a day after it rains. Remove your rear floor mats and check between where the carpet meets the plastic housing of the HV battery.

 

That is indeed a bummer.
I've read of missing body plugs the dealer didn't put in related to shipping.
You've looked in the spare tire well, under the foam? At least it's easy to get to.

 

Trunk area is dry. It's where my amplifiers live. Never noticed any water back there in any capacity and I've been in and out of there in all sorts of weather cleaning up or redoing wiring, different configs, etc. But the next extended reprieve from the rain I will double check.

Btw they are mounted on carpeted plywood which is attached to the trunk via an industrial adhesive. I am very much against destructive modifications due to the liability it would incur for warranty work. No cut wires, no holes drilled. Only hole I've put in the car is in a small easily replaceable part of the dash for a gain knob for my amp, part #5540647170C0.

IMG_1190 by soft_r posted Oct 24, 2025 at 8:21 PM

 

I'm thinking of a similar rubber plug like in your picture.
Perhaps some weatherstripping on hatch or rear doors?
How definitive was that pressure test?
There's always a smoke test...just kidding.

 

Might be the stinkin' payments? Like the new car smell, hate the stinkin' payment.