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GF07.16-P-2009P CDI Main Injection, Function



GF07.16-P-2009P CDI Main Injection, Function

Main injection follows preinjection. Main injection is controlled by the start of actuation (injection timing point) and the actuation duration (injection period). The main injection quantity is calculated by the CDI control unit (N3/9) while taking account of information from the following sensors:
- Rail pressure sensor (B4/6), for the rail pressure
- Boost pressure sensor (B5/1), for the boost pressure
- Coolant temperature sensor (B11/4), for the coolant temperature
- Charge air temperature (B17/8), for the charge air temperature
- Accelerator pedal sensor (B37), for the accelerator pedal position
- Crankshaft Hall sensor (B70), for the engine speed
- Fuel temperature sensor (B50), for the fuel temperature
- Pressure sensor downstream of air filter (B28/5), for the absolute pressure (vacuum) in the intake tract (except model 463)
- Pressure sensor downstream of air filter, right cylinder bank (B28/5), for the absolute pressure (vacuum) in the intake tract (only model 463)

Main injection for the fuel injectors (Y76) is not initiated by the CDI control unit if one of the following statuses is present:
- The engine speed is > 4500 rpm
- Fuel temperature limit exceeded
- The rail pressure is too low
- An external intervention in the quantity regulation, e.g. by the Electronic Stability Program (ESP) exists
- Engine is in the overrun
- The engine is switched off