What Should I Do If My Car AC Air Stinks?

Your car should always smell great, that’s why everyone uses air fresheners in their respective cars. Your car is a place where you enjoy your time. Any ride in the car that is smelling fresh and is clean as heaven can give your day a happy shot. A cool breezy ride can all of a sudden uplift your mood and give you a boost for the day ahead. But as soon as your turn on the air conditioner in your car you start smelling a foul smell in the car. There is where everything goes wrong, your mood degrades and the day planned ahead will be spoilt.

And your start wondering why is my car ac air stinks, read the article below to learn the causes and how do you fix your car’s ac, and make the air around you smell fresh and breezy.

Why Would The Car AC Air Stinks?

Whenever your car Ac starts to smell weird and pungent this is a sign that something is wrong with your air conditioner.  Let’s find out what can possibly go wrong with your AC that is making it stink badly.

1. Growth Of Mold And Bacteria Inside The Air Conditioner

One of the main reasons why there is a pungent smell coming out of the air from your air conditioner in the car is the growing molds inside your air vents. If you smell something of mildew in your car then that may be the cause of growing bacteria.

  1. As time passes and your air conditioner is overused a lot of microorganisms such as bacteria, mold, and fungi start to grow behind the dash panel on the evaporator.
  2. If your ac is not used for a long time then a lot of bacteria can grow inside your air conditioner.
  3. If you run your ac to the maximum then that may also cause the bacteria to grow because of excess water dripping in your unit.

2. Leakage of Gas From The Unit

The smell coming from the air thrown away by the ac can be the smell of your air conditioner gases, if so then your car’s ac is experiencing leakage of gas that is R22 and freon. The coolant leaking from an aircon rapidly evaporates into a gas. This gas is lethal and can cause nausea, and in some cases, even asphyxiation. The leaked gas can also lead to skin irritation and dryness as well as increased heart rate.

3. Dirty Air Filters Can Be A Major Cause

Dirt accumulates inside the air filters can make your ac to give away the air with a weird smell. The air filter must be cleaned properly so that there will be no dirt stagnant water, dust mite or other harmful pollutants be present inside the ac unit to damage the air coming out of the ac and give it a pungent smell.

4. Antifreeze Leaking Out Of The Unit

If there is a sweet smell coming around and you are nowhere near a sweets shop then guess what? it is your car’s ac that is smelling so sweet, but this could be a major issue since that sweet smell is the cause of your toxic liquid ethylene glycol also known as antifreeze. The leakage of antifreeze can be quite hazardous and the leak can come anywhere from the heater core, pipe or hose, coolant housing unit, or even the radiator.

How To Deal With A Bad AC Smell?

To deal with your car’s AC air that is stinking you need to follow the following steps:

  • If your problem is with the growth of bacteria what you can do? First and foremost diagnose the drain tube in your unit then make sure that it is working properly, Get an antibacterial treatment and use it behind your dash panel where the major growth probably is. This will destroy the bacteria growing over there. Turn off the car air conditioner and just let the fan run for some minutes after injecting the treatment solution into the air conditioner case. Running fan will help evaporate the water on the coils of your ac.
  • If you are experiencing a leak in your car ac you need to repair the leak. Check several areas where you can guess the gas is leaking from. You may inspect the fuel pressure regulator of your engine to see if the leak is in this area. You can also check the fuel injector “O” rings in the engine compartment for any leaks. It is also advisable to check your exhaust pipes and muffler for any holes that can cause gas leaks. You can even use a leak detecting can spray system that you just need to spray on your unit and that will easily show you the leakage spot. After diagnosing the area of the leak you may use some fixing clay to fix the leak. But it is still advisable to take your car to a mechanic for a leakage repair.
  • If the problem is there with the filter you may just replace the old filter with a new one and regularly clean the new air filter of your air conditioner unit, to avoid the same condition again.
  • If your antifreeze is leaking out then you should run to an automobile repair shop to get your ac fixed since it is not possible for you to fix this on your own also it is very dangerous to inhale that toxic gas.

Average Cost To Repair Your Car’s AC

The average cost to replace an air filter is up to $50 or more for one unit. The average cost for a cabin air filter is between $15 and $25. Whereas if you are dealing with leakage of gas or antifreeze then you may have to spend typically $150-$800 for minor repairs.


In conclusion, you now understand the answer to your question that was what should I do if my car ac air stinks, and how do you fix the ac unit and if not repairable on your own what is the average cost of repairing at any automobile center.  For precaution, you must always avoid turning your ac to maximum and not overusing it, also if it’s not the weather for ac turn it on for few minutes to avoid the growth of bacteria behind the dash unit. Also regularly clean your air filters so that dirt doesn’t accumulate that much that you have to replace it at some point.

Hope, this article solved most of your problems but if you are still having some question that is unanswered then don’t resist to type it down in the comment section below.

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