Volkswagen Marine SDI 55-5, Руководство пользователя

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Superior Technology
Internal functions in the engine control unit
With additional functions, the engine control unit
ensures the engine runs smoothly during
operation.
Idle speed control
Based on the engine speed signal that is supplied
5 times per crankshaft revolution, the engine
control unit recognizes even the smallest
deviation from the specified idle speed.
By way of changes in the metering adjuster
control, the engine control unit can maintain a
constant idle speed under all operating
conditions.
Smooth running control
In order to achieve particularly smooth, uniform
engine operation, the injection volume of each
cylinder is controlled in such a way as to avoid
output differences between the individual
cylinders.
This function is monitored by means of the signal
from the engine speed sender that supplies the
engine control unit with five signals per
crankshaft revolution. If the signals are received
in uniform rhythm this means all cylinders are
performing the same amount of work. If the
output of one cylinder is weaker, the crankshaft
will be accelerated to a lesser extent. If the
output of one cylinder is higher, it will accelerate
the crankshaft to a greater extent.
Once the engine control unit has recognized an
irregularity, a higher or lower injection volume is
immediately supplied to the corresponding
cylinder until the engine runs smoothly and
uniformly again.
The injection volume deviation is indicated in the
measured value block.
Engine electronic systems
MSSP_001_106