I don't think you're going to keep the smell from coming back, hence the reason there are products like Frigi-Fresh to clean up any mold from the evaporator coils. It gets damp, and most of the water should drain out through the bottom of the housing, but the coils are still cold and damp when you shut the engine off and the air stops blowing through them. Every car I've had gets a musty smell if you make a habit of turning the engine off with the air conditioning still on. One way to minimize it would be turn the the A/C off and let the fan run for a few minutes to dry things out before turning the engine off. I think you'll be very disappointed if you spend $$$$ to replace the evaporator only to find out it doesn't fix this problem.

 

You can buy the cleaner and clean it your self every 6 month

 

 

Run the AC and leave it running. .Pop the hood, and spray Lysol into the vents at the base of the windshield. If there's any mold, it should kill it. Also maybe change the cabin filter?

 

I did that on my wife's old Impala after I did the evap foam cleaning. Installed a HEPA cabin filter (Impala's located external at the base of the windshield). Never had a smell after that.

 

The cleaning through the evaporator drain tube is only temporary. The way to fully clean it would be to remove the evaporator and clean it that way, which is not a simple job. That's why it's ideal to prevent this issue from happening in the first place by running the fan with no A/C for a little while before reaching your destination.

 

Make sure when you turn the vehicle off that it is not in recirc mode. I know some of the newer vehicles, like my Toyota, that if you leave the system on "Auto", that it will open the recirc damper when turned off. I have fights with my wife on this all the time, as she sometime complains about a musty smell for a few seconds after startup when it is hot and humid out, and 100% of the time the Auto feature was not set. She tends to fiddle with blower speeds, etc. instead of just adjusting the temperature knob when it gets too cold, as that doesn't affect the Auto feature. We haven't had any issues since she is in the habit of making sure the Auto button is on before turning off the vehicle. Not sure if this generation of Pilot does the same thing, but if the recirc is on, which closes off air from the outside, creates a good breeding ground for funkiness in the evap core on hot days.

I've used Lubeguard Kool-It on my vehicles in the past. Usually do that when changing the cabin air filter, which should be removed and closed up before using. Went through the vents up top, and it does a decent job. Also used Frigi Fresh every now and then for that new car smell

 

Ozone Generator kills those things. Set it up inside. maybe take filter out and replace when done, put tray back in. climate control on higher front and back, let run like 30-45 minutes with OG on and vehicle closed up (they say a small amount of fresh air is good from slightly cracked window). Unplug OG, Open the doors and let it vent out for another 30 minutes with system circulating.

I bought that one to take car of anything left from my soaked carpet padding and the whole car smelling like mold/mildew BAD. Detailers use versions like that for smoke smells etc, hotels for the same thing in rooms.

full disclosure- I have not installed my carpet back in yet but it is sitting in my garage and does not smell that I can tell. After drying in sunshine I placed it in the Pilot when I ran the OG. Waiting in dealer to bring the vehicle in.