Change the in cabin air filter a few months ago, and I'll be DAMNED that cat's ass smell is back again . Got this ad from a local Dealer today. Has anyone cleaned their Evaporator Housing before? If so, how?

 

I have seen that type stuff used before- for cars that have moldy smell it does help.
The other solution is to turn OFF the ac a few blocks from home and run just fan - so it dries out the evap core-

similar to leaving the door closed on the washing machine al lth etrime after use will result in grime growth-
ask your wife or mom

 

iirc the demo on local tv news- you drill a small hole into the evap case and install the stuff direct- not for the faint of heart or unskilled with a drill~
but not difficult based on the demo
worth a shot, and pull the filters and inspect again- could be a cat really is using the intake vents for its business

 

If there is a chance of just buying a superior air filter I'll do it. Don't think the OEM filter is worth the $$.