I would remove parts until the evaporator is exposed then blow it out and/or vacuum it out then spray it down with Lysol.
Nope, that would be steam.
Call an AC contractor
wher is the a/c evaporator drain hose located
Either the a/c system is low on freon or the evaporator has an internal restriction....
The potential causes of a musty smell in AC vents include mold or mildew growth due to moisture buildup, a clogged air filter, or a dirty evaporator coil. To resolve this issue, you can try cleaning or replacing the air filter, cleaning the evaporator coil, and using a mold and mildew cleaner to eliminate any growth in the vents. It is also recommended to schedule regular maintenance for your AC system to prevent future musty smells.
you should change the AC air filter
The AC evaporator is located in the lower Dash.
Cleaning the evaporator isn't a regular maintenance item. They're mounted inside a sealed case, and in most cases you have to remove the dash to access it. Sometimes evaporators leak, preventing the AC from working and need to be replaced, but there's really no benefit to cleaning an evaporator on a car.
Condensate typically gathers on the evaporator and drips from a drain hole in the bottom of the heater box through a rubber tube to the bottom of the car. If the drain hole is plugged, the condensate can drip to the inside of the vehicle and even blow out the vents. See if you can locate the drain hole from underneath, and run something up there to clean out whatever is plugging the drain hole. You may need to get someone to help you locate it, or you could just find a vehicle similar to yours and see where the water drips out when the AC is running.
a starved evaporator.
yup, sign of a bad heater core
When an AC evaporator goes bad, it can lead to reduced cooling efficiency, causing the system to struggle to maintain the desired temperature. Symptoms may include warm air blowing from the vents, increased humidity levels, and potential leaks due to condensate buildup. In some cases, a malfunctioning evaporator can also lead to unusual noises or odors. If not addressed, it may cause further damage to the AC system, resulting in costly repairs.