Electronic fuel injector is also known as EUI, how does it work? Its working principle is simply that the electronic signal issued by the ECM is sent to the solenoid valve, which controls the opening and closing of the needle valve, thereby transferring a certain amount of fuel to the inside of the injector. The amount and duration of injection are precisely controlled by the ECM algorithm and MAP. The amount of fuel injection is determined by the injection time and the speed of the injector plunger, and is proportional to each other. The moment when the solenoid valve is powered is the beginning of the oil injection, and the loss of power is the end of the oil injection. Here are the specific four working steps of the injector.
Suction stroke
The fuel channel is connected to the engine cylinder head to deliver fuel through the cylinder head to the individual injectors, so the design of the fuel line must ensure that the fuel temperature is consistent between the injectors. After the fuel flows into the injector, the fuel is stored and cooled in the internal chamber, while the water and steam in the fuel are carried out. During this stroke, the injector plunger rises and fuel pours into the injector, filling the injector cavity.
Injection stroke
When the injector plunger begins to move down, the fuel beneath the plunger is forced out of the injector and returned to the fuel circuit. If the ECM does not signal the solenoid valve, then it will all return to the fuel circuit. When the ECM gives a signal to the solenoid valve, the needle valve controlled by the solenoid valve is closed, and the fuel can not return to the fuel circuit, and the pressure continues to increase as the plunger continues to go down, becoming a high-pressure fuel, forcing the nozzle valve to open and start spraying. The maximum injection pressure is not at the beginning of the injection, but near the end of the injection.
Remaining stroke
The injection continues until the solenoid valve loses power, at which time the solenoid needle valve opens, the high-pressure oil is relieved, enters the fuel circuit, and the injection valve is closed.
Post time: Jul-06-2023
