When some people think about cabin air filters, they conjure up images of summertime, air conditioning and musty smells. The reality is that cabin air filters work the majority of their magic when temperatures drop.
Every technician knows vehicle tailpipe emissions are higher when the engine is cold. You can smell these emissions in the air when a vehicle starts and is idling on a cold winter morning while you are scraping the window. During these cold starts, the engine is running rich and the catalytic converter has not yet started operating. These emissions are substantial to the point that what’s coming out of the tailpipe can be damaging to the driver’s respiratory system.