Working principle
The particles, water and other impurity in fuel will be filtered when getting through the medium which will cause the abrasion and other damage of precise instrument of the fuel channel system.

Fuel filter can be divided into fuel filter and diesel filter, most of passenger cars are adopting fuel filters, fuel filters include in-tank and external filters. External filters only existing in early stage, most of current cars are with in-tank fuel filter integrated with fuel pump. 

Fuel pump filter Structure:
It consists of housing, housing cover, filter element, seals etc. Wielding types: heat-board wielding, rotating friction wielding, vibration friction welding, laser wielding.

Hints:
1.As the mileage and duration increases, fuel filter will be running out it life cycle which will cause many malfunctions of vehicles like power loss, high fuel assumption, noise, performance degradation.
2.Choose high-quality fuel filter, inferior filter would cause problem with fuel supplying, power shortage. The impurities will cause damage to fuel injection system and fuel channel.
3.When there is obvious reduction in car speed and acceleration, then the fuel filter might be the root cause and need timely inspection.