What Is A Fuel Filter & What Does It Do?

A fuel filter is a usually shaped like a canister that contains many layers of filter for the fuel. They are a lot more important than you think, since the contaminated fuel can cause your engine to fail. Dirt, paint chips, rust, and even fuel contaminants can all cause the fuel to act differently within the engine. This hurts the efficiency of the engine and the pollutants in the exhaust.

Fuel filters are very effective at removing debris in the fuel, but it does mean that they will eventually clog up may lead to an expensive repair. The replacement of the part is usually part of a scheduled service that occurs at set mileages, per your manufacturer’s recommendations.

What Are The Symptoms Of A Bad Fuel Filter?

The vehicle doesn’t start
A partial blockage may mean the vehicle is difficult to start. The fuel filter may be so clogged that fuel is completely blocked from flowing to the engine. This will obviously mean the engine fails to start. Clogs in the fuel filter can lead to very expensive engine repairs, so be sure to get a mechanic to check it as soon as possible.

The engine stalls
A partial blockage will cause the fuel to flow unevenly to the engine. An uneven flow means the vehicle may drive smoothly sometimes, but will stall when stopped. This means accelerating from a stationary position may be difficult.

The vehicle performs badly at low speeds
A clogged filter may perform well at high speeds but can be caught out at lower speeds. This happens because the fuel pump is pushing the fuel more at higher speeds, which means it can slip through. At lower speeds the fuel has less pressure behind it so fails to get through.

The vehicle idles roughly
Rough idles are usually caused by the engine incorrectly combusting, which mainly is due to issues with the fuel. A blocked filter will cause issues with the air to fuel ratios inside the engine.