Air Filters

What is an air filter?

An air filter is part of the air intake system and is responsible for removing debris such as dust, leaves and other particles so that only clean air enters the engine. Clean air is essential for efficient fuel combustion however dirty air can cause expensive damage to the engine. A clean air filter can contribute to better fuel economy too. More air flow can mean less fuel us used to achieve the same power. Air filters are generally one of cheapest service parts to the increased fuel economy can lead to a filter paying for itself quite quickly.

There are three types of engine air filter:

• Paper air filter

• Foam air filter

• Gauze (fabric) air filter

How do I choose the correct engine air filter?

Like all replacement car parts it is best to obtain the original part number and compare to make sure that you get the correct one. In situations where it is not possible to obtain a part number often the correct filter can be chosen by the following:

• The W x H x D measurement of the filter

• The shape of the original

• Engine code

• Vehicle manufacture date (this is not the date the vehicle was registered but the date it was made)

• Engine number sequence (up to or after as specific number/letter

• VIN (chassis number) sequence (up to or after as specific number/letter

What brand of air filter should I choose?

There are hundreds of aftermarket makers that produce engine air filters so which one should you choose. Brands such as Bosch make air filters for the original car brands however there are a good number of high quality aftermarket brands of the highest quality and meet or exceed the original specifications. Brands such as Blue Print, Febi, Borg & Beck and Napa offer quality parts that are easy on the budget. The choice is down to your brand preference or budget.

How can I tell my air filter needs replacing?

Air filters are one of the parts that should be replaced based on the vehicle manufacturers recommended service schedule. There are circumstances where you might need to change the filter before that time.

Here are some symptoms of an air filter that needs replacing:

• Reduced fuel efficiency

• Check engine light is illuminated

• Inspection of the air filter shows it to be dirty (full of debris)

• Engine misfires or struggles to accelerate

• Black smoke or other harmful exhaust emissions