GF07.16-P-2008IB | CDI preinjection function | 10.9.99 |
ENGINE 628.960 in MODEL 220.028 /128
ENGINE 628.963 in MODEL 163.128
ENGINE 628.961 in MODEL 211.028
P07.16-2228-76
Functional diagram
B4/6 Rail pressure sensor
B11/4 Coolant temperature sensor
B17 IAT sensor
B28 Pressure sensor
B37 Accelerator pedal sensor
F1 Fuse and relay module
(model 163)
K40/7 Right front fuse and relay module (model 220)
L5 Crankshaft position sensor
N3/9 CDI control unit
N10/1 Driver-side SAM control unit with fuse and relay module
(model 211)
Y74 Pressure regulator valve
Y76 Fuel injectors
Y94 Volume control valve
Task
Reducing noise and pollutant emissions
The quantity injected required by the engine is subdivided into the quantity of pilot injection and the quantity of main injection.
Function
Start of actuation
The start of actuation of the pilot injection is calculated in line with the operating point, with the following data being taken into account:
last start of actuation of the main injection
coolant temperature
engine speed
vehicle electrical system voltage
Injection time
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Shutting off preinjection
The pilot injection is shut off in line with the operating point, if:
the moment of preinjection is exceeded
engine speed too high
preinjection quantity insufficient
main injection quantity insufficient
inadequate fuel pressure in the rail
if the engine is switched off
Calculating preinjection quantity
The quantity of pilot injection is calculated on the basis of :
engine speed
atmospheric pressure
coolant temperature
intake air temperature
rail pressure
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The coolant temperature, intake air temperature and the atmospheric pressure are used for correcting the quantity of pilot injection. The now determined quantity of pilot injection is removed from the quantity of main injection, in order to determine, if there is a sufficient quantity for the following main injection.
The rail pressure is selected so high, that a minimum quantity can be injected.
If the quantity of main injection is insufficient, the pilot injection is shut off.
CDI control unit, location/task | |||
CDI quantity control function | |||
Quantity control valve, location/task | |||
Rail pressure sensor, location/task/design/function | |||
Pressure control valve, location/task/design/function | |||
Injector location/Function/Design/Operation | |||
Coolant temperature sensor location/task/design/function | |||
Crankshaft position sensor, location/design/task/function | |||
CDI engine speed signal function | |||
Pressure sensor, location/task/function | |||
Pressure sensor downstream of air cleaner, location/task/function | |||
Pedal value sensor location/task/design/function |