Direct Petrol Injection System with Bosch Motronic MED 7 - Volkspage

Engine management
Engine torque implementation in the direct petrol injection system
The engine control unit uses the internal and external torque requirements to compute the target torque
and how it is to be implemented.
Implementation in stratified charge mode
In stratified charge mode, the target torque is
implemented via the injection quantity.
The air mass is of secondary importance because
the throttle valve is wide open in order to reduce
throttle losses.
The ignition point is of little importance because
of the retarded injection point.
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Implementation in homogeneous lean charge
mode and in homogeneous charge mode
In both operating modes, the torque
requirements are implemented in the short term
via the ignition point and in the long term via the
air mass.
As the air-fuel mixture in both operating modes
has a fixed lambda of 1.55 and 1 respectively, the
injection quantity is predefined by the air mass
and, therefore, is not used for torque control.
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