Fuel injector: sprays the pressurized gasoline from the gasoline pump in the form of atomization. The hole of the fuel injector is very small, so that the gasoline can be atomized better, but it is also easy to get clogged, so the fuel injector must be cleaned regularly. Nowadays, car engines are generally equipped with electronic fuel injection. The so-called electronic fuel injection is the abbreviation of electronically controlled fuel injection. The basic principle is that the engine control module calculates the best fuel injection timing and fuel injection amount based on the information from each sensor, controls the fuel injector, and injects gasoline to the end of the intake manifold, where it is then sucked into the cylinder by the engine and burned to perform work. Different from traditional carburetor engines, EFI engines can more accurately control the amount of fuel, have good atomization and sufficient combustion, which brings excellent performance, energy and fuel saving. However, the advancement of technology also has shortcomings. It is too complicated and maintenance is not easy.