Audi 4.2-liter V8 FSI, Обучение по обслуживанию

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Engine Management
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Engine management in the new 4.2L V8 FSI is by two
versions of the Bosch MED 9.1.1.
A single control module is used in the Audi Q7 engine.
There are two control modules for the RS4 engine. A
master-slave concept is required here due to the requisite
processing power at engine speeds up to 8250 RPM.
Further differences between the Audi Q7 and RS4 engines
with respect to engine management are as follows:
Engine Speed Sensor G28
An inductive sender is used in the Audi Q7 engine. A Hall
effect sensor is used in the RS4 engine with master/slave
concept.
The signal from the Hall sensor can, unlike the signal
from the inductive sender, be split with the result that it
can be utilized by both engine control modules.
Applying the signal directly to both engine control
modules ensures that the control modules are absolutely
synchronized.
Throttle Valve Module
The Bosch throttle valve module used in the Audi Q7 is
the largest in the range with a diameter of 82 mm. The
Pierburg system was selected because the air intake
system in the RS4 has a diameter of 90 mm. However,
both systems work in exactly the same way.
Spark Plugs
In contrast to the Audi Q7, spark plugs with a higher heat
rating (colder plugs)* are used because the RS4 engine is
subjected to higher thermal stresses.
* applies to NGK spark plugs
Injectors
Due to the higher fuel demand and the shorter window
of time available for injection at very high engine speeds,
the RS4 engine is fitted with larger injectors than the
Audi Q7 engine.
Diagnosis
The RS4 engine is diagnosed via the K-wire. The Audi Q7
is diagnosed via the powertrain CAN bus.
The processor operates at a clock frequency of 56 MHz.
The internal memory has a storage capacity of 512
Kilobytes. Each of the two external memories has a
storage capacity of two megabytes.
The connection to the vehicle network is made by means
of a CAN data bus.
In the case of the master-slave concept, data is
additionally exchanged across a private bus.
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