Bob, the only time an aftermarket CAI kit causes a CEL, is when an overzealous noob saturates the filter medium with oil. More IS better ain't it? Not in this case. None is best. A pre-filter is the way to go. I've used aftermarket CAI units on several rides, and I always cut enough of the foot out of a pair of used panty hose to go over the filter. It's cheap as hell, and really works.