Sometimes. I live in Decatur, Illinois where there are lots of stinky agricultural processing plants.

I didn't want it to sound like complaints about the rules...just was wondering what the logic was behind them. All noobs come up with stupid questions

But seriously. I did notice a little difference when I put that filter in...could have been partly because the old one was pretty clogged up. I probably would have noticed the same difference with an OEM filter.