Hello Joepan, on my 2008 CRV 4WD the arrow points down toward the floor. Just make sure on your replacement filter the arrow is pointing in the same direction. Its usually printed on the paper filter material itself. If using a reusable K&N filter, I don't think all K&N filters have an arrow or direction stamped into the rubber but one way it fits nice and solid into the cabin air filter tray (correct way) and if you have it upside down (incorrect way), the filter will have a lot of flex in it. I'm attaching a photo that shows the air flow direction as it is printed on the cabin air filter door. Hope this helps.What is proper arrow direction for replacement,Some non oem products have conflicting directions.