Port Fuel Injector
The port fuel injector is a small, precise solenoid valve. When the ECM supplies a ground to the port fuel injector circuit, the coil in port the fuel injector is energized. The energized coil pulls the ball valve back and allows fuel to flow through the port fuel injector into the intake manifold. The amount of fuel injected depends upon the injection pulse duration. Pulse duration is the length of time the port fuel injector remains open. The ECM controls the injection pulse duration based on engine fuel needs.