Do these filters require that the filter media be reoiled? And if you use too much oil, how does it affect the MAF?
K&N's do require cleaning and re-oiling periodically. Too much oil can be messy, but unlikely that it will mess with the sensor.
This is from K&N's website:
K&N Response to Mass Air Flow Sensor Concerns
We are aware of the “urban myth” (K&N News Story
) created by a few dealerships that a vehicle's MAF sensor can be contaminated by K&N filter oil. No evidence has ever been provided to support this “myth” and three years of diagnostic testing by K&N has shown that not only is this allegation not real, it is not even possible. In our opinion, it is an excuse for a dealership and/or the vehicle manufacturer to avoid a legitimate warranty repair. In the last 4 years, we have sold over 10,000,000 lifetime air filters and received only a few hundred calls from consumers who are having dealership or service provider challenges. We believe that Dealership's or service provider's real incentive may be to discourage the use of reusable products so they can sell disposable products over and over. In order to provide consumers with added comfort that they will not be placed in a bad position by an improper warranty denial, we offer our Consumer Protection Pledge