This damn musty smell!

I did the roof rails off ... in the snow on the roof it is a lot of work .. take it off the rails .. snow slides easy ...
the covers are using a plastic tool ...I also did dish soap to spray the covers and then the covers pop off ....

the Toyota window seals .. seals shrink then the doors are in the water .. I used a sealer to seal up the cracks on the window seals ..

 

IN the 4th gen at least, there is an AC drain line behind the passenger glove box, that can clog and lead to moisture build up...Might be worth looking into.

 

Well I think I got it. Three treatments over a few days of Lysol in the fan box, windshield intake, and drain. Blower and heat on all positions after each treatment and then a box fan on the opened cabin filter hatch for a day. Smell is significantly better, if it lingers at all I think it's just in my nose.

 

I literally just went through this with my wife’s 2019 Sienna. Damn smell drove us crazy. Checked everything possible. Sunroof drains, all AC drains, etc. Ended up figuring out the windshield had a leak. Top corner was leaking and running down the inside of the pillar, down the firewall, through electronics, and under the floor. Headliner never got wet. Carpet never got wet, only the padding underneath. Toyota kept trying to say they couldn’t find anything. Well my son and I took everything around the windshield apart, he doused it with a hose while I searched. Sure enough, there it was! Took it back to Toyota, with all the trim removed and showed them. They replaced the windshield, and deep cleaned the entire interior. All is good again! Happy wife, happy life!