Fuel Injector: Description and Operation

Fig. 60 Fuel Injector:

The fuel injectors are small solenoids mounted on the fuel rail. They allow fuel to be injected into the intake manifold. The injectors receive the ground circuit from the ECU in terms of "Injection Duration". The voltage applied to the electrical windings pulls the needle valve up, allowing fuel to flow through the nozzle.

WARNING: The positive circuit is always "Hot" at the injector terminals when the battery is connected.