5/28/19

Why does my car ac smell?

1.Mold or Mildew in the System

  • Most common cause.

  • Moisture accumulates in the evaporator coil or ducts, creating a breeding ground for mold and mildew.

  • Smell: Musty, damp, or gym-like odor.

2. Clogged or Dirty Cabin Air Filter

  • The cabin air filter traps dust, pollen, and debris. Over time, it can develop mold or just start to smell if not replaced regularly.

  • Smell: Stale, dusty, or musty.

3. Bacteria Buildup

  • Organic material (like leaves or insects) trapped in the AC system can lead to bacteria buildup.

  • Smell: Sour or vinegary.

4. Refrigerant Leak

  • A chemical smell can indicate a refrigerant leak.

  • Smell: Sweet or chemical-like.

5. Rotting Debris in the Air Intake or Vents

  • Leaves, animal nests, or even dead animals (like rodents) can get into the ventilation system.

  • Smell: Rotten, foul, or dead animal smell.

6. Burning Smell

  • If the smell only occurs when using the heater or AC fan, it might be due to electrical issues or overheating components.

  • Smell: Burning plastic, rubber, or oil.

What You Can Do:

  • Replace the cabin air filter (cheap and easy first step).

  • Run the fan without AC for a few minutes after use to dry the evaporator.

  • Use an AC cleaner spray (antibacterial cleaner) into the air intake vents.

  • Have the system inspected by a mechanic if the smell persists or is chemical/burning.

go to https://www.youtube.com/watch?v=NeH5WoSOCW4 for a video version