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GF07.16-P-3008P CDI Overrun Mode, Function



GF07.16-P-3008P CDI Overrun Mode, Function

In overrun mode at an engine speed > 1600 rpm and without depression of the accelerator pedal, actuation of the fuel injectors (Y76) is interrupted (zero delivery). To do this, the CDI control unit (N3/9) reads in the following information:
- Accelerator pedal sensor (B37), accelerator pedal position
- Crankshaft Hall sensor (B70), motor speed

In the overrun, the CDI control unit interrupts the actuation of the fuel injectors and lowers the fuel pressure in the rail via the quantity control valve (Y94) and the pressure control valve (Y74).

If the accelerator pedal is depressed again or the engine speed falls below 1600 rpm, then the so CDI control unit re-actuates the fuel injectors and increases the fuel pressure in the rail via the quantity control valve and the pressure regulator valve.