2000 gmc savana bad smell in the air conditioner?

[casey]

what could a mildew smell be from coming out of the airconditioner vents

 

[goldwing127959]

This smell is from standing water in your air.
There is a small drain that is in the engine compartment back by the fire wall. This drain gets stopped up and will not allow the water to drain. Locate it and poke a pencil into it. The water will now drain and the smell will disappear.

 

[Uncle Red]

That would be from the moisture build up in the A/C condensor housing.
DO this.
1. Turn the A/C on but NOT MAX.
2. turn the fan on high.
3. Mix a combination of Mr Clean and water in a 5 gallon bucket. Heavy on the Mr Clean.
Pour this solution slowly into the air intake (passengers side) at the bottom of the windshield. it will fill and drain out the overflow and kill the mold and musty smell.
Be prepared to roll the windows down as the car will smell Mr Clean Clean.

 

[amercnphsyco]

The smell is usually similar to the smell of dirty gym socks and it means the air conditioning filter needs to be replaced.