The Volkswagen air filter makes it possible for your vehicle to breath clean air for an extended period of time. This is accomplished by the filter element in this intake system component removing the particulates that would interfere with the engines operations. The Volkswagen air filter and cleaner box are placed at the front of the intake system to prevent any debris from entering the combustion chamber that could have a negative effect on the internal explosion that occurs there. As time passes and miles are placed on your Volkswagen, the air filter will become obstructed with the debris it has trapped. As this occurs the MAF sensor in this intake will relay the reduction in the air flow to the onboard computer so it can make an accurate calculation on the air to fuel mixture required by the engine. As the number of particulates the air filter traps increases, the onboard computer compensates for the reduced air flow to the Volkswagen engine. This compensation can only go so far before the performance and mileage are negatively affected by the blockage. The typical time a Volkswagen receives a new air filter is during a tune up. This is also the time the fuel filter is changed. For most vehicles this is an annual event that is on the owner's periodical maintenance schedule. An extra step many owners take to help their vehicle breath is to inspect the air filter and cleaner box at about the midpoint between tune-ups. This is when the filter element is pulled and the larger debris is shaken out of it to help improve the air flow to the engine. In many instances the spark plugs are also pulled and cleaned. Both steps help to improve the performance of the engine.