How often should the fuel filter be replaced and at what mileage?

[VanFelicity]

For externally mounted fuel filters, they should be replaced approximately every 20,000 kilometers. Built-in fuel filters typically require replacement every 40,000 kilometers. Below are the hazards of not replacing the fuel filter for an extended period: 1. Difficulty starting when the engine is warm: Issues such as faulty ignition coils, dirty throttle bodies, or spark plug problems can cause difficulty starting a cold engine. However, if starting is also difficult when the engine is warm, it may indicate a fault in the fuel system. 2. Severe loss of engine power and shaking while driving: A clogged fuel filter can lead to low fuel supply pressure, reducing engine power. It may also cause low injection pressure, resulting in a lean air-fuel mixture, incomplete combustion, and symptoms like shaking while driving. 3. Idle shaking: As the fuel filter begins to clog, it can gradually reduce fuel pressure, making fuel supply increasingly difficult. Insufficient fuel pressure can cause the engine to shake at idle.