Alfa Romeo 159 Training Material page 114

ENGINE
Self-learning
The ECU implements self-learning logic in the following conditions:
installation of a new injection ECU
installation of a new throttle actuator
removal/refitting of engine speed sensor or phonic wheel for misfire acknowledgment.
The throttle learning settings are maintained also when the battery is disconnected. The misfire acknowledgement
phonic wheel settings on the other hand are lost.
System self-adaptation
The ECU is provided with a self-adaptive function which acknowledges changes in the engine due to settling in time
and ageing of components and the engine itself. There are two adaptation functions for two intervention plans:
minimum and user.
Cold start-up control
Mixture is naturally leaner during cold starts due to low fuel evaporation at low temperatures and higher engine oil
viscosity. The engine ECU acknowledges this condition and corrects the injection time according to:
coolant temperature
intake air temperature
battery voltage
engine speed.
Spark advance is controlled according to the engine speed and engine coolant temperature only.
While cranking, the ECU controls a first simultaneous injection for all injectors (full-group injection) and after starts
normal sequential, timed operation after acknowledging the cylinder stroke.
When the engine is warm, the ECU governs the throttle to control the amount of air needed to keep the engine running.
The engine speed is decreased as the engine temperature increases to obtain nominal values when the engine is warm.
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