The smell is likely from mold/condensation forming in the exterior vents.

When I bought my G it had the same problem. I popped the hood and sprayed a bunch of lysol in the exterior vents, and then changed the cabin filter, and the smell was completely gone.

 

Yeah, I am not sure if the system goes through the evap/heater core and then through the cabin AF or the other way around. Would be worth knowing since you dont want to just soak your cabin filter.

 

What kind of Lysol are you all using for this? And it could be likely about the mold seeing as how Texas morning create an @$$ ton of moisture every single morning, coupled with pollen and dust/dirt...very likely breading ground for mold.

 

What kind of shade-tree back-yard mechanic are you going to? He needs a swift kick in the ***. If he doesn't know the answer regarding to the location of the cabin filter all he had to do was go to google and search it, rather than make up some bull ****.

Un-educated mechanics like him is what gives REAL automotive technicians a bad rep.

 

Try the Ozium -spray a bunch of it inside and close all doors and windows but run the car with the air recirculating in the cabin. Maybe spray some into the vent near the windshield wipers with the ac/heat on

 

A few years ago on my old G coupe I tried Ozium. It's great stuff (bought a two pack, used one) but the duration of that solution was short-lived. The real solution is to purchase Frigi-Fresh or Klima Cleaner foams that you inject to clean the evaporator coils to rid it of mold/mildew/nastiness. Change your cabin filter at the same time!

Remove passenger glovebox/footwell parts as if you're changing the cabin filter. Find the inlet from outside (or inside if you prefer), insert tube until is stops at the evap coils. Unload the can gradually. After a while the foam will clean the coils and drain itself out beneath the car. Use some Ozium or a disinfectant with the system running hot with all vents open (car doors too!). Replace cabin filter and reassemble.

I'm sure there's a DIY either on here or g35driver.com but that's it in a nutshell minus pics.

 

Totally agree with this method. After spaying it let to run for a minute and let it sit out in the sun for a couple of hours. Always works well for me.

 

I'm in Tucson, AZ and intermittently have this same issue, so definitely not only humid areas part of the country with this problem. Lysol along with remembering to go to Fresh Air instead of Recirc for the last few minutes of my drive. This seemed to really help for a good few months but it seems its time again as the smel is starting to come back.