Fuel Injector: Description and Operation

Fig. 9 Fuel injector:

The injector is mounted on the branch portion of the intake manifold. The injector receives the pulse signal from the control unit, and injects the fuel toward the intake valve in the cylinder head. The injector operates on the solenoid valve principle. When a driving pulse is applied to the coil incorporated into the injector, the plunger is pulled into the solenoid, thereby opening the needle valve for fuel injection, Fig. 9. The quantity of injected fuel is in proportion to the duration of the pulse applied from the control unit.