Understanding Your Vehicle's Fuel Filter and How It Works

When most drivers think of filters, they envision the engine air filter. Combustion engines have an air filter that, as the name suggests, filters contaminants from the air that enters the combustion chamber. The air intake will bring in fresh air from outside the vehicle into the engine's intake manifold. The air will pass through the filter, after which it will enter the combustion chamber. But vehicles have other types of filters, such as a fuel filter. 

What Is a Fuel Filter?

A fuel filter is a device that's designed to remove dirt, debris and other forms of contaminants from the fuel. Combustion engines don't just burn air; they burn a combination of air and fuel. The air will pass through an air filter before entering the combustion chamber, whereas the fuel will pass through a fuel filter before entering the combustion chamber. They both serve the same purpose of filtering contaminants, but air and fuel filters are designed for different substances.

How Fuel Filters Work 

Most fuel filters fall under one of two categories: container-styte or cartridge-based. Container-style fuel filters consist of a tank-like container made of plastic or metal. Cartridge-based fuel filters, on the other hand, contain a filter cartridge.

Whether container-style or cartridge-based, all fuel filters work the same. Upon cranking your vehicle, the fuel pump will transfer fuel from the tank to the engine. The fuel filter sits between the tank and engine. As the pump begins to move the fuel, it will force the fuel through the fuel filter. Any contaminants in the fuel will then be removed. The fuel filter will collect and hold these contaminants so that they don't enter the engine's combustion chamber.

With a clean fuel filter, you can expect the following benefits:

• Less wear and tear on engine
• Improved gas mileage
• Smoother idling
• Lower risk of engine misfires
• Cleaner exhaust

When to Change Your Vehicle's Fuel Filter

How often should you change your vehicle's fuel filter exactly? Like with other forms of automotive maintenance, you should refer to your owner's manual. Some automakers list changing the fuel filter as a form of regular maintenance, whereas others do not. 

If your vehicle has a container-style fuel filter, you may not need to change it. If your vehicle has a cartridge-based fuel filter, on the other hand, you may need to change it once every 30,000 to 100,000 miles. Regardless, your vehicle's owner's manual should reveal if and when you need to change the fuel filter.