Fuel Injector: Description and Operation

FUEL INJECTORS

Fuel Injector:

The fuel injectors are 12 ohm electrical solenoids.

The injectors are positioned in the intake manifold with the nozzle ends directly above the intake valve port.

The injector contains a pintle that closes off an orifice at the nozzle end. When electric current is supplied to the injector, the armature and needle move a short distance against a spring, allowing fuel to flow out the orifice. Because the fuel is under high pressure, a fine spray is developed in the shape of a hollow cone. The spraying action atomizes the fuel, adding it to the air entering the combustion chamber. The injectors are positioned in the intake manifold.

FUEL INJECTORS - PCM OUTPUT
The fuel injection system uses bottom feed injectors. Fuel enters the bottom of the injector from a passage in the intake manifold. The Auto Shutdown (ASD) relay supplies battery voltage to the injectors. The PCM controls the ground paths to the injectors. By switching the ground paths on and off, the PCM can fine-tune injector pulse width. Injector pulse width refers to the amount of time an injector operates. The PCM operates all injectors.

The PCM determines injector synchronization from the camshaft position sensor and crankshaft position sensor inputs. The PCM grounds the ASD and fuel pump relays after receiving the camshaft position sensor and crankshaft position sensor inputs.

The PCM energizes the injectors in a sequential order during all engine operating conditions.