After heavy rain the car vents smell musty for the first couple of minutes. The smell fades once the air conditioner runs. I replaced the cabin filter recently, and the footwells feel dry, but I haven't checked the evaporator drain. I'm wondering whether moisture is lingering in the HVAC housing rather than entering from outside. What's the sensible diagnostic order before paying for a cleaning treatment that might only mask it?
A musty smell from vents after rain
Safety-critical vehicle advice should be treated as general discussion; use qualified repair help when a fault could make a vehicle unsafe.
- car-repair
- musty
- smell
- vents
1
3 replies
Check the drain first. If the evaporator pan isn’t emptying cleanly, the smell can show up right after rain or humidity and vanish once the...
Check the drain first. If the evaporator pan isn’t emptying cleanly, the smell can show up right after rain or humidity and vanish once the system dries out.
I’d also look for a plugged cowl intake or leaves sitting where they shouldn’t. People jump straight to mold cleaner, but water path issues come first.
Mine turned out to be the drain tube, and the carpet still felt dry. The smell was the only clue, which was annoying.