Fuel Injector: Description and Operation

Fuel Injector Construction:

PURPOSE
The injectors are electrical solenoids that control fuel flow.

LOCATION
mounted between the intake manifold and fuel rail.

CONSTRUCTION
The injectors are a solenoid-actuated constant-stroke pintle type consisting of a solenoid, plunger needle valve and housing.

OPERATION
Each time power is applied to a fuel injector the pintle pulls up a preset amount and fuel is sprayed directly at the intake valve. Since fuel pressure and pintle lift are constants, by changing the amount of time ground is applied to the injector coil (injector duration) by the ECU, the amount of fuel delivered can be precisely controlled.