So my wifes car has a mildew smell comin from the hvac system. I replaced the AC filter and it smelled normal for 1 day. She turned the AC on and still no smell but then she turned it off and it came back. Think about taking the rain tray off and taking a look down there for debris that may be stuck in the system.

Any one else been down this road?

 

nevermind..I found the solution.

 

So what was it and how did you fix it? Please share. Thanks