How do you know it's time for a change?

It will vary a great deal.  If you live where there is a lot of dust or pollen or ….  Then change it often.  If you live where the winds bring in clean air, then change less often.  There will be a great deal of difference depending on where you will be driving.

Another reason to inspect the air filter once a year at the very least is to see if something has gotten into there that shouldn’t have.

We frequently hear stories about how mice love to build nests in car air boxes, and chew up the air filter. Well, if you have this happen, you can then have a mouse nest, or worse yet, and actual mouse sucked into your engine.

Not the best thing to have happen to your car.