Do you spray both sides of a K&N filter?
No, do NOT spray both sides. Only spray the side which faces the outside air source, NOT the side that faces the MAF sensor.
Which way should arrow point on air filter?
The arrow on your filter should always face the unit and away from the return air duct that carries the air that will be heated or cooled. HVAC systems push the cool or warm air out and pull spent air in, recirculating the air throughout your home.
What happens if I don’t oil my K&N filter?
K&N filter elements have larger holes than stock air filters to allow more air through. The trade off is that without the oil, those larger holes would let in more dust type particles which, as anyone who knows engines will tell you, is not good for the engine.
Do you oil inside and outside of K&N filter?
After you have cleaned BOTH sides with the cleaner and then rinsed it off, let it air dry and then spray the oil on BOTH sides. Let it air dry for 20 minutes and then recheck it for spots that may need more oil. It should be an even red on both sides. 1 of 9 found this helpful.
How do I know which way the air flows in my AC?
Generally the edge of the filter is marked with an arrow which points in the direction of the airflow. In other words, the air travels from the tail of the arrow toward its point. If there is no arrow, the side that is stronger or reinforced by cardboard or wire mesh is the side the arrow should be pointing to.