Can I clean my K&N air filter with soap and water?
Can I clean my K&N air filter with soap and water? The degreaser should be applied liberally to the filter. Warm soap water is a good way to use it. It's okay to scrub it with your hand or a plastic bristle brush. Can I clean my K&N air filter with WD40? The question this article wants to answer is, could you use WD40 to re-oil your K&N air filter? (or any other oil-based performance filters). Quick answer – no, you should not use WD-40 to oil your air filter because they dry up too quickly and leave behind residue...