FUEL INJECTOR
DESCRIPTION
The injectors are positioned in the intake manifold with the nozzle ends directly above the intake valve port.
OPERATION
The fuel injectors are 12 volt electrical solenoids. 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 or
two streams. The spraying action atomizes the fuel,
adding it to the air entering the combustion chamber.
Fuel
injectors
are
not
interchangeable
between
engines.
The PCM provides battery voltage to each injector
through the ASD relay. Injector operation is controlled
by a ground path provided for each injector by the
PCM. Injector on-time (pulse-width) is variable, and is
determined by the PCM processing all the data previ-
ously discussed to obtain the optimum injector pulse width for each operating condition. The pulse width is con-
trolled by the duration of the ground path provided.
PM
FUEL INJECTION
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