Fuel Injector: Description and Operation

COMPONENT DESCRIPTION
The fuel injector is a small, precise solenoid valve. When the Engine Control Module (ECM) supplies a ground to the injector circuit, the coil in the injector is energized. The energized coil pulls the needle valve back and allows fuel to flow through the injector into the intake manifold. The amount of fuel injected depends upon the injection pulse duration. Pulse duration is the length of time the injector remains open. The ECM controls the injection pulse duration based on engine fuel needs.