The fuel under pressure, coming from the pump, creates a thrust on the rotor (1 and 2) countered by the calibrated spring (3).
When the set pressure is exceeded, the plate valve (4) moves and the excess fuel is fed from the tank through the nozzle (5).
To keep the pressure stage constant on the injectors, the difference between the pressure of the fuel and the atmospheric pressure must be constant. This is obtained by connecting the calibrated contrast spring seat with the atmosphere, using a connector (A).
Intake air circuit
The air circuit consists of an intake manifold, a throttle body and an intake unit. This circuit also includes an absolute pressure sensor and an air temperature sensor positioned on the fixed frame on the left side of the headlamp support. The throttle position potentiometer is fitted on the throttle shaft.