****************************************************************************************** K&N FILTER CLEANING*******************************************... Show more***********************************************SO K&N recommends that you clean your filter every 50,000 - 100,000 miles (based on dirt build up) on a street driven car. If you live or drive frequently on a dirt road or use your car off road, you need to clean it sooner. You need to buy the K&N filter cleaning kit. Substitutions are NOT recommended. The K&N kit is specifically formulated to not damage the cotton gauze of the filter when cleaning and provide a recharge of the tacky oil that traps dirt on the filter surface. Autozone and Summit carry the kit. Basically its a s simple as following the directions that come with the kit...Here is ours... (though it was probably not quite ready for cleaning... However, we were having some drive-ability concerns and I needed to rule the filter and mass air out.)BEFORE AFTER Show Less