I disagree with with karjunkie about using a k&n filter,,this type of filter uses a cotton guaze contained between a wire mesh.
The cotton guaze is coated with a special oil,,the oil in combination with cotton guaze,,traps dirt particles.
When you purchase a filter such as this,,you also need to purchase a cleaning-renewal kit,,
this filter needs to be cleaned occasionally and when the cleaning is done, the filter needs to be re-oiled.
Therein lies a potential problem,,if the filter is not oiled adequately enough,,then you may have an air filter that provides less than 100% filtering efficiency.
On the other side of the coin,,if too much oil is applied to the filter,,then a portion of this oil,,under the pressure of intake vacuum,,will leave the filter and coat in a fine oil mist,,everything downstream,,including the,,maf.
When the maf elements get coated with this oi,,the sensor will not work correctly.
Then the sensor will need to be removed and cleaned.
In essence, a plain old stock paper air filter will work just fine.
A k&n air filter is a good choice,,minding you are prepared to be fussing over you car more.
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