Engine Air Filter Change

I would worry that since the filter isn't a perfect fit, dirty air could be getting by and entering the motor.

Urban areas can actually have very dirty air, especially with all the dust on the roads, the diesel exhaust, etc. When I still had my home in the burbs, I had an HRV that would suck in "fresh" outside air.

I started using MERV 12 rated filters on the HRV, with a charcoal prefilter. After 30-45 days the white media would be jet black with dirt, dust, and diesel exhaust. It was a bit better in winter when the roads were frozen and covered with snow/ice.

Worst was dry summer, all the home construction would have dust everywhere.