Fuel Injector: Description and Operation

The injector is of the solenoid-actuated constant-stroke pintle type. The injector consists of a solenoid, plunger, needle valve and housing. When current is applied to the solenoid coil, the valve lifts up and pressurized fuel fills the injector. Because needle valve lift and fuel pressure are constant, the injection quantity is determined by the length of time the valve is open. The injector is sealed by an O-ring and seal ring at the top and bottom. These seals also reduce operating noise.