The fuel filter removes contaminants from petrol or diesel before they reach the engine. A clogged fuel filter causes hesitation, loss of power, and difficult starting. Diesel vehicles often have a combined fuel filter/water separator. At CarParts247 we stock fuel filters from Bosch, Mann-Filter, and Mahle.
A restricted fuel filter starves the engine of fuel, especially under load. Diesel filters also separate water from the fuel — ignoring the water-in-fuel warning can damage injectors.
Most manufacturers recommend fuel filter replacement every 30,000–60,000 miles, though diesel filters may need changing more frequently. Always prime the system after fitting a diesel fuel filter.