Check the drain hose if it is plugged it will keep the moisture in and it will grow mold. If the mold is real bad you may have to remove the cover and wash the core with a mild bleach solution. I use an engine spray nozzle. If you can dump a gallon of weak bleach solution in the inlet ducting quickly, that may help.
Just a thought!
If cleaning and checking the drains doesn't fix the issue there is a procedure in the service manual for dealing with A/C smells that involves spraying a coating (YN-29) on the A/C evaporator coils. It's not a TSB or recall, but should be covered under the regular warranty or the premium ESP if they are applicable.
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