The injector is a very critical component in the gasoline electronic injection device. It controls the final injection of fuel. If something goes wrong, the engine will not work normally or stop working immediately.

If the injector is installed in the original position of the carburetor and combined with the throttle, this form is called single-point electronically controlled fuel injection. Its advantage is low cost and simple maintenance. The disadvantage is that the distance between the injection point and each cylinder is The uneven distribution of fuel will lead to uneven fuel distribution, and fuel will easily stick to the wall of the intake pipe when the cold engine is started.

If the injector is installed on the intake pipe of each cylinder, this form is called a multi-point electronically controlled fuel injection device, which is the form used by most current gasoline electronic injection engines. Its advantage is that each cylinder has its own injector, and the injector is as close to the intake valve as possible, avoiding the disadvantages of single-point electronically controlled fuel injection. The disadvantage is high cost and complicated maintenance.

At present, most automobile engines use multi-point electronic injection, and a small number of economical cars use single-point electronic injection. If an old carburetor engine is converted to electronic injection, single-point electronic injection will be used.

Generally, the electronically controlled gasoline injection device in automobiles consists of three parts: fuel supply part, air supply part and control part. The fuel supply part consists of a fuel tank, a gasoline pump, a gasoline filter, a pressure regulator and a fuel injector. The gasoline pump draws gasoline from the fuel tank and filters out impurities through the gasoline filter. The pressure regulator pressurizes the gasoline to a pressure higher than The negative pressure in the intake manifold is sent to the injectors of each cylinder through the oil pipe. The injector is equivalent to a switch, and the component that controls the switch is the ECU (electronic control unit).