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1.05L REVOTORQ ENGINE
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B. AN OVERVIEW :
Engine Management System Overview :
Modern engine management systems do
a fine job of ensuring that engines run cleanly and
efficiently in a wide variety of conditions, they are
for the most part reliable and require little or no
maintenance.
Engine management system Comprises
of Electronic Control Unit (ECU), Sensors,
Actuators, Wiring Harness and control algorithms,
which determine the performance of the Engine
as a whole and as part of the vehicle.
Electronic Control Unit (ECU) :
The Electronic control Unit is a 32 bit
microprocessor which controls the injection
parameters as well as some of the vehicle related
outputs such as Fan, AC drivability in gears, EGR
etc.
The ECU receives input from various
sensors located on the engine and the vehicle,
and decides the injection quantity, injection timing,
number of injections best suited for the engine to
work with maximum efficiency and safety.
Input to the ECU is received from Crank
sensor, Cam sensor, Vehicle speed sensor, Pedal
sensor, Rail Pressure Sensor, Fuel Temperature
sensor, Coolant temperature sensor, Air mass
flow sensor, Boost Pressure and atmospheric
pressure sensor, water-in-fuel sensor, pump
mounted sensor.
Based on all these inputs, the ECU
controls all the injectors directly. It also controls
the Inlet metering valve on the High pressure
pump, Engine cooling Fans, Air conditioning and
Exhaust Gas Recirculation (EGR) valve.
The injection parameters are corrected for
various atmospheric conditions like cold and hot
climates and different Altitudes. Corrections are
also applied considering engine safety in case of
faults and any abnormal overheating. Fault
detection is made simple. Faults are recorded in
the ECU which makes it easy to be read with the
help of a diagnostic tool and to find a solution.
Sensors :
A sensor is a device that measures a
physical quantity and converts it into an electrical
voltage which can be read by an instrument or
used by some controller for its purpose.
Actuators :
An actuator causes an action (say injector
open or close) based on command given by ECU.
Wiring Harness :
Engine Wiring Harness and Vehicle
Wiring Harness interface the Engine and Vehicle
components to Engine Control Unit.