Iveco daily euro 4, Repair Manual

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82
ELECTRIC/ELECTRONIC SYSTEM D
AILY
E
URO
4
Base - March 2006 Print 603.93.651
EDC16
Electronic injection control
The system calculates injection on the basis of the
processing of the following parameters:
-
Engine rpm
-
Engine coolant fluid temperature
-
Intake air capacity
-
Battery voltage
-
Fuel pressure
- Accelerator pedal position
Fuel pressure ranges from 400 to 1350 bars (1600 for F1
engines), according to engine rpm and load operating
conditions.
The lower pressure is compensated by longer injection
times and vice versa, always taking account of the loads
required.
Up to 2800 rpm pre-injection is also carried out in order to
reduce the typical noise of direct injection.
Pre-injection advance angles, the distance between
pre-injection and main injection and advance angles of main
injection vary according to the instantaneous engine
operating conditions.
System diagnosis is performed by means of diagnostic
instruments (no Blink Code is used).
Immobilizer recognition
When the control unit receives the signal of the key on
”MAR” it communicates with the immobilizer control unit
to enable starting.
Checking fuel temperature
With the fuel temperature greater than 75
°
C, detected by
the sensor on the fuel filter, the control unit operates the
pressure regulator to decrease the line pressure (injection
times are not changed). If the temperature exceeds 90
°
C,
the power is reduced to 60%.
Checking engine coolant temperature
The control unit, depending on the temperature:
- of the engine coolant, turbocharging air and fuel,
operates the electromagnetic fan (Baruffaldi) and
switches on the coolant temperature warning light.
Checking quantity of fuel injected
According to the signals from the sensors and the mapped
values, the control unit:
-
operates the pressure regulator;
- varies the ”pilot” injection time to 2200 rpm;
-
varies the ”main” injection time.
-
Checking idling adjustment
The control unit processes the signals from the various
sensors and regulates the amount of fuel injected:
-
it operates the pressure regulator;
-
it varies the injection times of the electro-injectors.
Within certain thresholds the speed takes account of the
battery voltage.
Fuel cut-off in release phase
In the phase of releasing the throttle pedal the control unit
actuates the following logic elements:
-
it cuts off supply to the electro-injectors;
- it partially reactivates supply to the electro-injectors
before reaching idling speed;
-
it operates the fuel pressure regulator.
Checking cylinder balancing on idling
According to the signals received from the sensors, the
control unit controls the regularity of the torque at idling
speed:
- it varies the amount of fuel injected into the single
electro-injectors (injection time).
Checking regular engine rotation (anti-sawing)
It ensures regular engine rotation at a constant rate while
increasing revs.
The control unit processes the signals received from the
sensors and determines the amount of fuel to be injected via:
- the pressure regulator;
-
the electro-injector opening time.
Checking smokiness at exhaust on acceleration
With heavy acceleration, on the basis of the signals received
from the air introduction meter and engine speed sensor, the
control unit determines the optimum amount of fuel to
inject:
-
it operates the pressure regulator;
-
it varies the electro-injector injection time.
Checking exhaust gas recirculation
Depending on the engine load and the signal from the
accelerator pedal sensor, the control unit limits the amount
of air taken in, actuating partial suction of the exhaust gases.