Musty smell when AC is on

Hi everyone! I have a 2019 TRD and there has been a musty smell coming from the AC since I bought it. Any ideas?

 

Needs an evaporator core cleaning. Toyota sells a kit for cleaning.

 

Have you changed your cabin filter recently? That can also produce smells.

 

https://www.youtube.com/watch?v=dS8MOVjmDbw

 

Change your cabin Air filter .
Run the Toyota evaporative core cleaning and spray kit.
Switch off AC 5 mins before arriving at your destination.

 

What I had to do:

Whack it with KOOL-IT/some other brand evaporator cleaner. (needed some paper towel shoved into the HVAC drain tube to seal it and prevent the cleaner from spraying back out.)

1/2-2/3 can of Lysol sprayed down the vents beneath the wipers and also into the cabin air filter box. (fresh air, fan high, cabin air filter removed)

My cabin air filter is fine in my case but it’s also a common culprit so swap it if you haven’t changed it recently like me.

I’ve read/watched about the turn-off-AC-early procedure but I’m running a personal experiment to see if I can get away just leaving it on fresh air instead and treating it normally otherwise.

So far making sure it’s on fresh air and not recirculate most of the time and especially when turning off the car has gone alright.

you don’t want the system to be parked and sealed in recirculate, letting the moisture inside cook. Heard it might reduce drainage too by virtue of not letting air in to replace the water as easily.

Update: Leaving on fresh air and not turning off early seems to have worked fine so far. It could’ve been another chemical I handled but wear gloves with the cleaning spray up the drain tube.

 

Ya just spray some air in the AC drain tube. Worked on the Corolla, prob do it every tire rotation.

 

To keep it from happening again, or to prevent it from happening to begin with, shut off the compressor five or so minutes from shutting it down while keeping the fan running. That way the ductwork has a chance to warm up and keeps from forming condensation that pools and grows mildew. Sure, you may be a little uncomfortable for a few minutes, but your vehicle won't end up smelling like a public shower in the Caribbean lol.

 

I had both the heat and fan on max for 10 minutes in high summer and the smell went away.