How to fix damp/mildew smell?

shadow191

Premium Member
Premium
Location
Atlanta, GA
Car
2007 FX35
So in the last month or so, every time I start up the FX, there is a damp/mildew smell coming from the AC vents. It goes away a few minutes into it, but it's there every time the fan starts blowing. What might be causing this? It just started one day without any warning. Is it the cabin filter? I just swapped it out less than a year ago. The car is always garaged and there weren't any major rainstorms so I'm not sure what might have gotten wet.
 
maybe its time to change the cabin filter again. try the ones with charcoal in it. might help a bit. i got to change mine also
 
You need to change the cabin filter at least twice a year. Plus you can spray Lysol into air vents if you want


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Guess I'll change it. Just weird because the old one had been in there for who knows how long and there never was any smell.
 
The new filter will help initially but I think I remember hearing that the root of the issue might be that the refrigerant needs to be cleaned out and recharged. There may also be mildew build up in the canister.
 
I had this smell a few years ago. I changed the filter, but first I sprayed Lysol liberally through the fan and into the vents with the air blowing on high. This killed off the smell and the new filter kept the system clean. 1Z makes a AC cleaner called Klima-Cleaner that foams into the vents and does a little bit better job than the Lysol method if you don't mind spending $15 dollars on a can of spray cleaner.
 
I am having this problem on my '07 FX35. I replaced the filter which helped for a few days. Then I pulled the filter (still clean and dry) and sprayed Lysol. That helped for a few days then the odor returned!

Could it be a clogged drain in the ventilation system? Perhaps the A/C condensation is not draining properly???
 
I just swapped the filter yesterday. Original filter was actually really clean, so it doesn't look like this was the culprit. Strangely, after I made the post the smell went away before I ever did anything. So it may be as some have posted mildew building up somewhere else in the system and then it dried out. If it comes back, I'll investigate further. Not sure how refrigerant could be the cause since that part is kept separate from the air itself at all times.
 
Besides changing the cabin filter with a carbon activated filter you can try turning your AC off a short time before you shut engine off to help clear moisture from system.
 
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