Replace The Air Filter on a 2012 Honda CR-V
The Engine Air Filter, sometimes called the Engine Air Cleaner Element, is an essential part of your engine, as it protects your engine from accumulating dust and other things that are floating in the air. Honda suggests you replace it every 30,000 miles under normal conditions, but it couldn't hurt to take a look at it every oil change to see if it needs changing.
Pop the hood.
Release the three clips holding the air box lid on. There is one on the right, and two on the left.
Lift up on the lid and slide it to the left slightly to release it from the tab on the right.
Remove the old air filter and insert the new one in exactly the same orientation. The diagonal edge should be facing the front driver's side of the car.
Slide the lid into the tab on the right, press it down, and re-attach the clips.