Why Your Cars A/C Smells Musty
Your car’s A/C is meant to cool you down on a hot day, but sometimes it’s just too much when that cold air quickly transforms into an unpleasant smelling breeze that’s just not pleasant to breathe in. Your car AC’s sudden unruly smell can be a result of several different issues. But do take note that it can be hard to pinpoint the cause of the smell and get it fixed without contacting auto repair professionals.
Dirty Evaporator
If your car’s A/C smells musty, it may be caused by a buildup of mold and bacteria on the evaporator coil. This happens when dirt, dust and other particles settle on the evaporator coil over time. This muck can be blown up into the cabin through the vents. Fortunately, there are some easy ways to defunk your car’s air. One way is to use a disinfectant like Lysol and spray it in the car’s air intake, which is called the “plenum.” Then, run your vehicle’s fan on low. This process will kill the bacteria and the musty smell will go away. But this will only work if the evaporator drain is clear and your air filter isn’t dirty or clogged with debris.
Dirty Air Filter
If you’ve ever gotten into your car with the A/C on, you may have noticed a strange smell that’s not pleasant to breathe in. This is because it’s a sign that your A/C isn’t delivering air to your engine properly. One of the main culprits is a dirty air filter. When an air filter becomes clogged with dirt, it limits the amount of oxygen that’s being delivered to your engine. This causes the air-fuel mix to change, which can cause the engine to misfire or fail to start. The result is a buildup of soot residue that covers the spark plug tips and makes them unable to fire correctly. Depending on the severity of this problem, it can also trigger your check engine light. Getting your engine’s air filter replaced can help solve these symptoms and prevent the engine from throwing a code.
Dirty Plenum
Your car’s A/C system combines refrigerant gas (R134a or R1234yf) with air that’s pumped through ductwork into the interior of your vehicle. Once inside, it recirculates the cool air through a series of components to maintain a consistent temperature in your vehicle’s cabin. A key part of this system is the plenum, or air distribution box. It’s one of the most important parts of an HVAC system, as it serves two critical purposes. The plenum supplies the air that’s pushed into the ductwork in a home with HVAC equipment. It also houses an air filter that traps dirt and other contaminants. If the plenum becomes dirty, it can reduce the flow of air through the ducts and make the system work harder than it should. This can damage the ducts and coils, which can lead to problems with your air conditioning.
Dirty Condenser
As we’ve discussed, your car’s air conditioning system uses refrigerant to cool the air inside your vehicle. The evaporator, compressor, condenser and ductwork all play a role in creating that cool air. When these components are dirty, the air is less effective at transferring heat from your car to the outside. This decreases the cooling power of your air conditioner and increases your energy bill. A dirty condenser coil is one of the main causes of this problem. Dirty condensers can have a huge impact on your electricity bill, so it’s important to have your AC serviced regularly. The first step to removing musty smells from your car’s A/C is to spray plenty of cleaner in the plenum intake vent. This is located at the base of your windshield where your wipers are. With the engine on and the interior fan running, you should be able to pull the cleaner into the system where it will kill any bacteria and remove the musty smells.