On a hot summer day, nothing beats the comfort of a car’s air conditioning. But what should you do if the air coming out of your vents is foul-smelling? I’ll show you how to get rid of mildew smell in car AC in this article.
What Makes Car AC Smell Bad?
In a nutshell, wetness. The air conditioning system in your automobile does not produce cold air; instead, it removes heat and moisture from the air outside of your vehicle, making it feel considerably cooler than the air around you.
The AC unit’s coils concentrate the heat and moisture in the air, removing the humidity before delivering the cooled air to your vehicle.
Hot air moving into the unit can cause moisture pockets that surround the condensing unit in your AC system, resulting in small pools of water that are discharged outside of the car via the drain line.
However, if moisture becomes stuck inside the AC unit and the air vents or cannot find its way out, the water will collect inside the unit and around the coils, causing dampness inside the AC unit.
How does mold grow in your car AC?
If your drain line is clogged or you use your air conditioner regularly, the unit is likely to be moist, providing a perfect living condition for mold and bacteria.
The foul odor will be carried inside your automobile by air that travels through the evaporator. And the mold build-up on the unit. Mold is the most prevalent cause of obnoxious odors from your car’s air conditioning system.
Bacteria, mildew, and other unwelcome microorganisms can increase as vehicles age. The growth of these bacteria inside your car’s ventilation system can be accelerated if the AC unit is not used frequently or used excessively.
Mold thrives in your car’s air conditioning system because it is always humid and dark, ideal conditions for mold to thrive.
How to Get Rid of Mildew Smell in Car AC
A disinfectant spray is the most straightforward technique to get rid of mildew in your car’s AC. And your intuition about getting it out was correct! If you smell mold in your automobile, getting rid of it is critical for your health. Mold can be harmful.
Here’s what you should do:
- Start your automobile.
- Turn the air conditioner up to its maximum setting. Then, instead of air recirculation, use the outdoor air mode.
- Spray the disinfectant for around 15 seconds on the air intakes outside the car near the windscreen.
This should take care of the mold. If it still smells musty after a few days, repeat the process.
How to Prevent Mildew Smells in Car Air Conditioning
Here are some suggestions:
Turn off the air conditioner. Before turning off your vehicle, leave the fan on for 2-5 minutes. Every time you use the air conditioner, it will dry much more thoroughly.
Replace or clean your air conditioning filters. Dirty air filters restrict airflow and allow moisture to build up inside your air conditioner. Ensure to update your vehicle’s air filters as recommended by the manufacturer.
In the outside air vents, spray an antiseptic (where your car pulls air from outside into the car from). Make sure your air conditioner is adjusted to take air in from the outside so that the spray is drawn into the ventilation system and may directly kill mold and bacteria.

Hi, My name is Ollie Barker.
With 25 years working in repair and detailing shops. I’d love to share my tips & tricks to all car lovers. Also, give my recommendations on which products are the best to have on the market.
Thanks for visiting CarDetailingArt! Hope you enjoy your time on my little blog!