Instrument injector

The electronic control unit directly controls the heater plugs control unit managing the pre and post heating times mainly according to the values for the engine coolant temperature and the intake air temperature.

In order to calculate the post-heating times, the control unit also assesses the accelerator lever position and rpm values, decreasing these times if there is a high engine power request.

1. Electronic control unit
2. Accelerator lever position sensor
3. Air temperature sensor
4. Rpm sensor
5. Coolant temperature sensor
6. Heater plugs control unit

Instrument injector

The instrument injector informs the electronic control unit of the actual injection advance (start of the injection stage or of the start of the movement of the needle valve).

According to the signal the control unit corrects the advance set by the injection actuator until the nominal value is reached.

The injector is fitted on the cylinder (1) and is equipped with a device for recognizing the exact moment of the start of the injection stage and with wiring for sending a signal and informing the electronic control unit.

Inside the injector there is a coil (2), a needle valve 93) and an adjustment pin (1). The coil is electrically supplied and produces a magnetic flow which affects the needle valve (3). When the latter initiates the opening of the nozzle for injecting the fuel, this causes a variation in the magentic flow in the coil (2) which the control unit recognizes as the start of the injection and on which the advance adjustment strategy is based.