Hyundai Repair: musty smell, refreshment service, funky smell

Question
2006 sonata why is the car having a really nasty funky smell only when the ac is on,dealer told me the cabin filter was changed and a spray was used, still smells bad!

Answer
Hello Terry,
Usually smell caused by mold. Some of the mold passes filter and gets landed on the evaporator core. If that is the case replacing micron filter will not help it. Only way to get rid of that smell is to have an A/C refreshment service done.