I just bought a 2003 C230 and was going to put a K & N Air Filter on it.

Is this worth doing?

http://www.ajusa.com/cgi-bin/knfilte...df25e1a4da7ae0

 

For at least 10 plus years, I have used K&N in all the family cars, clean them twice a year, and never had a problem with check lights. I recently installed a CAI which has a K&N filter in it. Does a K&N OEM give more HP, I don't really know. But if you buy one. disconnect the ground on the battery for 1/2 this will reset the MAS as they do suck in more air then stock. But don't forget to reset, you 1 touch windows ESP ARS, Sunroof and a couple other things, it is in the owner manual how to do. When I had a Porsche Carrera I bought a lot of performance product from AJ USA, they are good people.