Fuel Injector: Description and Operation

Fuel Injector:

PURPOSE
The fuel injector atomizes and meters high pressure fuel delivered to the engines intake system.

OPERATION
The injector always opens the same distance. Fuel pressure is maintained at a constant value by the pressure regulator. The amount of fuel delivered by the injector depends on the amount of time that the nozzle is open. This is the injector pulse width: The time in milliseconds the injector nozzle is open.

The Powertrain Control Module (PCM) activates the injector solenoid causing the pintle to move inward off the seat, allowing fuel flow through the orifice. The amount of fuel delivered by the injector depends on the amount of time that the injector nozzle is open.

CONSTRUCTION
The stainless steel electro-mechanical device consists of:

- A solenoid

- Needle and valve assembly.

The solenoid has an armature and a needle or ball valve with a spring holding the needle or ball closed against the valve seat.

The flexible fuel injectors have a higher fuel flow rate than unleaded gasoline injectors and are methanol compatible.