Fuel Injectors

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The PCM controls fuel injector "on" time (pulse width) to meter fuel quantity into the intake ports. The PCM receives inputs from several engine sensors to compute fuel flow necessary to maintain correct air/fuel operation throughout engine operating range.

Each cylinder has a solenoid-operated injector that sprays fuel toward each intake valve. Each injector receives battery voltage from the main relay. A PCM-controlled ground circuit is used to complete the circuit and energize the injector. Fuel injectors "fire" sequentially (in engine firing order) once per complete cycle.

Injectors consist of solenoid-actuated pintle and needle valve assembly. The amount of fuel delivered to the engine is regulated by length of time the solenoid is energized (pulse width). The atomized spray pattern is obtained by the shape of the injector pintle.