Car air conditioners can develop a bad smell for a number of reasons. The most common cause is bacteria build-up in the evaporator coils. When the air conditioner is turned on the coils start to collect moisture. This moisture provides an ideal environment for bacteria to grow. Another common cause of bad smells from car air conditioners is mold growth. Mold can grow on the coils or in the drain pan.
The best way to prevent bad smells from developing in your car air conditioner is to regularly clean the evaporator coils. You can do this by removing the panels that provide access to the coils and using a brush or vacuum attachment to remove any dirt or debris. It’s also important to empty the drain pan and make sure it’s clean and free of mold. If you notice any mold growth you should clean it with a bleach solution.
