Why Are My Car Vents Blowing Smelly Air?

Does turning on the A/C on a hot day fill your car with a strange smell? Air conditioning circulates air throughout the vehicle's cabin to regulate the temperature. Under normal circumstances, this air has no scent. If you're picking up on foul odors, it could signal problems with the ventilation or other parts of the vehicle.

These problems could have various causes, such as mechanical or electrical faults. It's essential to investigate the source of these strange smells for the health of passengers and the safety of the motor vehicle.

There's A Leak

Leaking chemicals are a common cause of strange or foul smells from the A/C. As air circulates in the cabin, it blows in fumes from the engine bay. Common examples include oil leaking from hoses, gaskets, or the oil filter and antifreeze leaks in the cooling system.

Oil leaks have a burning smell caused by oil getting into contact with hot engine parts, while antifreeze has the sweet scent of ethylene glycol. Fixing the leaks gets rid of the smell.

Mold Growth In Vents

For older vehicles and those in humid areas, bacteria may grow in parts of the A/C system like the evaporator, where moisture collects. It causes a musty, moldy smell that gets blown into the car's cabin when you turn the A/C on. You can combat this with vent cleaners to eliminate the foul odor.

If the problem is more serious, you may need to get a full system inspection and repair at an auto care shop.

There's A Problem With The Electronics

Nowadays, most cars have electronic systems to control engines, sensors, and other vehicle parts. If you're getting a burning plastic smell when you turn on the A/C, they're likely caused by an electrical fault. Maybe it's a short, burning wire, or too much debris collected in the vents.

You can't tell what it is using your nose, so it's best to take your car to an auto shop for inspection.

Maintenance And Repair Of A/C

If you need car A/C repairs in Walnut Creek, CA, give Roesbery Car Care a call today!