aquarian

I am sure many of you have experienced this. When the A/C is on, there is no smell. When it's off, you smell mold. Where exactly should I spray the A/C cleaner into to get rid of the smell?

tenspeed

Mold grows where it's wet which means it probably down by the heater core. I would try removing the cabin filter and spray towards the box. You might want to replace the filter if it's not fresh.

Can you run the fan when spraying? That would suck the mist through the system but it might also spew it out the vents... Good luck.

aquarian

Thanks. I have read some Audi instructions online and you are supposed to turn the engine on, have the system recirculate, turn the temperature down, and no AC.

The filter should be removed, and depending on the product that you use, you can spray into the vents, and into the air intake at the passenger footwell.