At my car’s last routine servicing, the workshop replaced the air filter. The filter has never been replaced. Is it necessary to have it replaced?
The air filter in the engine compartment serves to filter the air that is drawn into the engine.
It is important that air entering the combustion chambers is clean, not only to maximise the oxygen content but also to prevent any abrasive infiltration that could have an impact on the cylinder walls.
There are plenty of minute airborne particles and soot in the air and the filter stops these foreign particles from entering the intake manifold and hence the combustion chambers.
Over time, the filter gets choked and while it may continue to stop dust flowing in, the spaces that allow clean air to enter will become restricted.
A dirty air filter can cause loss of power and an increase in fuel consumption.
Air filters are relatively inexpensive (usually costing less than $200) and it would be advisable to replace them at least every 25,000km.
You could also clean the filter with a vacuum cleaner. If it is the washable type, you can wash it with an air-filter detergent that you can buy from accessory shops.
Most original air filters are not washable, but there are washable replacement filters which cost a little more.