For fuel filters, the recommended replacement cycle should vary according to the structure, performance and use of the filter. If the filter is installed in the fuel line, it is called an external filter. Conversely, the internal filter is a filter installed inside the fuel pump and fuel tank. The fuel tank filter, or its protective sleeve, is generally considered a maintenance-free component.

For most car manufacturers, the recommended replacement cycle for normal maintenance of their external filters is 48,000 km, and the recommended replacement cycle for conservative maintenance is 19,200 to 24,000 km. Refer to the owner's manual for recommended replacement cycles.

In addition, when the filter hose appears aging or cracks caused by dirt, dust, oil and other dirt, it is necessary to replace the hose in time.

The fuel filter of many imported cars uses a drum tube connection. In order to ensure the reliability of the connection seal, the same gasket cannot be used repeatedly, in addition, even if a new gasket is used, the tightness of the connection must be tested. When the fuel system needs to replace the O-ring, it is necessary to ensure that the O-ring specification is accurate, and to check whether the elasticity and hardness of the ring are appropriate.

The loopless fuel system has only an internal filter (in the fuel tank). Although this multi-in-one pump, filter, delivery unit is expensive, but when the fuel delivery is blocked or the engine performance is reduced, it must be timely and proper maintenance and maintenance. At the same time, it is also necessary to check all fuel line faults, and cracks and flanges at the hose clamp.