Mildew/Musty Odor from AC vents--2006 Honda Pilot

I recently purchased a used 2006 Honda Pilot. I now notice a mildew/musty smell that appears to come from the ac vents. I only notice it when driving with the windows down, right after I turn the AC off, and sometimes when I first get into the car. I do NOT notice it when the AC is running or when the fan is blowing. I have had the car detailed twice (thinking the odor was coming from the upholstery) and have hired someone to spray an odor eliminator spray into the vents and air intake. I have also changed out the cabin air filter. None of these actions have helped and the smell remains. I love the car but this odor is really annoying me. Please let me know if there is anything else I can do to get rid of this odor, or if I will just have to live with it. Thank you!!

The smell is likely to be from mildew growing in the HVAC vents.
I suggest that you do the following:
Spray a goodly amount of Lysol spray disinfectant or a specialized HVAC sanitizer (Frigi-Fresh is one brand) into the HVAC intake which is located outside, at the base of the windshield. Turn on the HVAC fan in order to pull the mist through the ducts. Repeat in a few days.

If this doesn’t help, then the only solution would probably be to disassemble the dashboard in order to access and remove the ducts for a thorough cleaning with bleach. However, this would be a VERY pricey proposition, based on the amount of labor involved.

If it is the interior you would notice it before you turn on the AC when you first get into the car. You could try activated charcoal tied in some old pantyhose and placed under the seat. You can get it at a pet store for cheap. It will absorb the odors. Swap it out every few weeks until the smell is gone. It may be that some one left the window down and the carpet or insulation has mold. That would be a more expensive fix, removal and replacement. I would try the cheap fixes first.

Pilot_Guy, I have the same exact problem with my 2006 Honda Pilot. I noticed the smell very shortly after getting the car, which makes me think it’s a manufacturing problem.

It’s a 12 year old car, which has had 12 hears for mildew and mold to grow.

Why would you think it’s a manufacturing problem? Just because two cars out of the hundreds of thousands have this problem? In any case, it’s up to you to fix it, the manufacturer has long since opted out.