How To Clean And Re Oil A K&N Air Filter on a Any Car
K&N Air filters use an oiled cotton gauze construction. This article covers cleaning and re-oiling a K&N air filter. K&N suggests you inspect your filter for service every 25,000 miles.
K&N Cleaning Interval
How often do I need to clean my K&N air filter? K&N suggest cleaning the filter as soon as any portion of the wire screen material is not visible. With panel filters in good road conditions, they say this will probably be about 50,000 miles (cone filters closer to 100,000!). Needless to say, people typically clean them more often. The one in this article had about 40,000 miles.
MAF Sensors and K&N Filters
It is important to note that modern cars that use a Mass Air Flow (MAF) sensor require special care when re-oiling these types of filters. If over-oiled, the oil can end up on the sensitive wires of the MAF and cause it to incorrectly measure air consumption. This can lead to a check engine light and to lean air/fuel mixtures.
Paper filters do not have this problem, and honestly filter very well without losing a noticeable amount of power. If you're not up for the re-oiling procedure, just buy a quality paper filter and change it regularly.
Quick Steps to Clean a K&N Air Filter
Remove the Air Filter From the Car
If your K&N air filter (or similar oiled filter) is still installed in the car. There may already be a guide here on HowTune for your car. If not, help the next guy by writing a guide, HowTune will split the ad revenue with you.
Cleaning a K&N Air Filter
Shake any loose dirt and debris out of the filter.
Use the cleaner spray from the K&N Filter Recharger Kit. Spray the filter on both sides with a substantial portion of cleaner.
Let the cleaner sit on the filter for 10 minutes. Do not let it dry.
Wash the dirt out of the filter by rinsing water into the clean side, out the dirty side.
Use low pressure water from an open-ended hose or faucet.
Let the filter completely dry before oiling
Re-Oiling your K&N Filter
There are 2 different recharger kits, one has a spray, the other just pours onto the filter. I prefer the spray. Remember, DO NOT OVER-OIL the filter. You want just enough for it to wick evenly into the filter, giving it that pink K&N color.
- Spray Oil: Spray evenly across the filter surface like you would with spray paint. Error on the side of too little oil. I spray from a distance of 8-10 inches (creates lighter mist). Moving quickly, I spray one side of the pleats, then the other till there are no areas without pink oil. Do the same for the back side of the filter, I usually spray even lighter on this side.
- Drip Oil: Apply oil on along the tops of each pleat. Given a little time, the oil will spread into the filter.
Let the oil wick into the filter for about 20 minutes.
If there are any dry or splotchy areas, lightly apply more oil to that area. The filter should appear evenly oiled at this point. Let sit for another 20 minutes if more oil is applied.
Clean off excess oil from the rubber or filter housings. Using the spray will leave quite a bit of oil on the filter's edges. I use a paper towel to soak up any extra oil on these surfaces.
Once you're satisfied with the results, re-install your filter back into the air box. You should be good to go for a while!