Bosch ECU MS 25 Sport Manual page 23

2.4.3 Hydraulic System and Components
Bosch Motorsport
Matching signals for the calibration above. Blue=crank, red=cam, yellow=cylinder 1 pres-
sure, green=cyl 1 Injector energizing.
2.4.3.1 High Pressure Pump and Fuel Metering Unit FMU
The characteristic curve IFMU_FLOWNORM (Fuel Metering Unit nominal curve), used to
calculate the current equivalent of FMU flow ratio, is very important for correct rail pres-
sure controller behavior under any engine operation conditions.
Either current-less open or closed type metering units can be used. ECU measures actual
current for metering unit and the control strategy is current control.
Calibration example for typical CP3 pump
2.4.3.2 Injector Energizing Profile
Injector energizing (current profile) must be correct for used solenoid injector type. The
current profile has several different calibration parameters, but the three most important
parameters are different current levels for booster, pickup, and holding current, which can
be calibrated in the injector initialization function.
Engine Control Unit MS 25 Sport
Starting up the ECU | 2
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