Air Filter

I changed stock air filter to KN today noticed another filter( prefilter I guess) If that is what it is do I need to change also and what intervials? With this prefilter what is the fuss about oil from Kn filter messing up map sensor, How could it .

 

That 'other' filter...doesn't need changing that I know of. Most people take it out completely. I took mine out.

K&N filters are oiled filters. When you first put them in, they should be fine. But when you ever go to clean them, be careful not to over-oil them. If you over oil it, the oil can get on the MAF sensor. Also, you need to make sure the filter is seated properly in the airbox. A lot of people complain about that also.

I've run K&N's for years...in different vehicles. I cleaned mine once every 6 months. If they get dirty - they won't filter properly either.