Is there a strange smell in your car, especially when the air conditioner or heater is on? increase.

The odor is probably due to condensation coming from the evaporator in the heating and cooling system. Basically, water collects in that area and if it sits long enough, it will develop a musty smell.

Most of the water is discharged outside the vehicle through the evaporator drain under the vehicle. Have you ever seen a small puddle of water under your car? However, if that water collects in the evaporator and stays there for a while, it can develop bacteria and mold, causing odors.

The good news is that the solution probably doesn't require a trip to the mechanic.

First, turn off the fan and open the window. From an auto parts store he gets a disinfectant such as Lysol or his A/C sanitizer and sprays it into the climate system air intake (also called a plenum).

The plenum is located below the windshield where the wipers are located. From there the air comes and enters the heating and cooling system.

With the engine on and the interior fan running, spray a large amount of cleaner on both sides of the plenum intake, and the fan will draw the cleaner into the system, killing bacteria and removing musty odors. Leave the windows open to let the air out of the car.

If you have a cabin filter, remove it before spraying the sanitizer so you can move around the system. It may also be a good time to replace a dirty filter, as it can interfere with optimal airflow, and doing it yourself can save you money and time.

Another source of odor can be your sunroof. There are small drainage holes on the sides that can get clogged from time to time, allowing water to seep into the roof liner or even drip onto the seat.

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