Filter specialist MAHLE has highlighted the importance of precision fitment in relation to a popular ait filter fitted to many Fords, Volvo and Mazda models. The MAHLE LX 1780/3 air filter element has built in anti rotation protection to assist technicians in the fitting process and according to the company offer many advantages many over alternatives.

Every air filter element has greater flow resistance around the pleated paper joint compared with the rest of the filter, as it acts as a seal. If the air mass flow meter is in close proximity to the filter element, the air flow volume will vary depending on the position of the pleat, which could lead to incorrect data being sent to the engine management system. It is therefore imperative for the replacement filter to fit in its designed position.

If the element is replaced and not installed in its correct position, the air flow may differ and the engine warning light may come on, prompting the driver to take the vehicle for repair. It is not uncommon for technicians to assume the problem is with the air mass flow meter, which will be replaced and calibrated, appearing to solve the problem. However, this is incorrect because when the filter element is replaced again and installed with the pleat in a different position, a faulty reading will recur.

In order to consistently achieve the same, or near identical, flow conditions in the filter housing and therefore enable reliable air flow metering, MAHLE has equipped one of the end plates of its air filter insert with a patented alignment lug that fits exactly into a recess housing. This means that only MAHLE replacement filters can be inserted in the correct pre-determined position, which cannot rotate once inserted.

This design requires a precise fitting procedure, as the intake pipe must be removed from the air box prior to the replacement. This will provide enough ‘give’ for the housing to flex and allow the filter to be eased into place. The technician can also visually check that the filter element has been correctly inserted by ensuring the lug is in the recess. 

MAHLE says this is a prime example of how using a MAHLE OE filter has many benefits, simplifying the fitting and maintenance process due to its easy installation, nullifying the need for recalibration and increasing customer satisfaction.