Originally Posted by Fen335i
Curious, what's the downside of not changing this once a year? Poor/stagnant smell coming through A/C vents? Poor ventilation/airflow? Reduced life on cabin heating/AC system?
A/C stank comes from the evaporator core already inside the car. The best way to alleviate that is to turn off the A/C button a few minutes before you turn the car off so as to dry it out.