The lifespan of the filter depends on the amount of debris it traps.

A filter that is made to last 40,000km may have a far shorter lifespan if the vehicle is driven in a dusty environment.

But regardless of the mileage, a filter should be replaced before airflow is restricted; symptoms include power loss and high fuel consumption.

Then again, you should not replace filters too frequently.

A slightly dirty filter works better than a brand-new one.

Automoblie Association of Singapore

This article was first published in The Straits Times.

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