Fuel Injector: Description and Operation

PURPOSE
The eight fuel injectors are electro-mechanical devices which both meter and atomize fuel delivered to the engine. They are mounted in the intake manifold and positioned so that their tips direct fuel just ahead of the engine intake valve.

COMPONENTS
The injector bodies consist of the following:
- solenoid
- needle and valve assembly
- director/metering plate

OPERATION
An electrical control signal from the Powertrain Control Module (PCM) activates the fuel injector solenoid causing the needle to move inward, off the seat allowing fuel to flow. Since the fuel injector flow orifice is fixed and the fuel pressure drop across the injector tip is constant:
- fuel flow to the engine is regulated by the length of time the solenoid is energized.
- atomization is obtained at the point where the fuel separates at the end cap.