Car Air Conditioner Smell: Is It Mold?

Enjoying a nice Sunday country drive is great, as long as you don't get a big smell of dirty socks, or a cat urine smell coming from your car air conditioner.

A smell coming from your car air conditioner is not uncommon. Many people have this problem, and many people wonder if the smell is mold. The answer is most likely "yes." However, the smell could also be a residue built up of another odd smelling item, such as cigarettes. Although this is not something we like to hear, it needs to be fixed. Below you can explore different suggestions, and recommendations on how to fix this smell.

It Grows

Mold and mildew need 3 sources to grow. Moisture, food, and very little or no air flow. When your ac is turned off, it becomes a breeding ground for mold and mildew.

Give It a Good Cleaning

Before you try anything too extravagant, try this simple remedy. Wash the inside of your car. Not a simple clear out the trash and vacuum, but a good detailing. Use soap and very warm water to wash your doors, and dashes. Clean the upholstery of your car as well. This may not make all of the smells disappear but it will be a great start.

Change the Filter

If the smell is simply not just an odor that has landed somewhere in your car, but rather something like mold in your ac, try changing the filter. Cars have filters that filter the incoming air. Over time the filter attracts dust, dirt, and debris. As the filter goes from wet to dry, and back again, it breeds bacteria. If you are currently smelling mold, it may be a little more than just changing the filter to get rid of the smell, but this is one of the first steps you will want to take.


Many people will use a bacteria killing aerosol to spray in the vents. You will want to let it sit about 30 minutes, and then start your car, and let the AC run.

Soaked Paper Towel

Take a paper towel and soak it in white vinegar. Place the soaked paper towel in a zipped baggie and set it in your car overnight. The bag and the contents in it should help soak up the smells that shouldn't have been there in the first place.

Baking Soda

Simply sprinkle some baking soda on your car mats. Baking soda, just as used in your refrigerator will absorb any smells that should not be present. Leave the baking soda on for awhile before vacuuming your floor mats.

Replace the System

This will be the very last option you will want to take. However, it may just have to be done. If you have tried about everything you could possibly think of, you may have to simply replace the system. Remember, usually there are other options out there, so try those first.

Whether the smell is from something that has been in there that shouldn't have been, or it is mold, hopefully after trying these options, your car is back to that new car smell.