Iveco Daily. Manual

75537

Intake exhaust
gas

Hot exhaust gasses

Engine coolant

Cold exhaust gasses

Air flow meter

1. Connector - 2. Flow meter body - 3. Air and

recirculated gas inlet mesh - 4. Suction air temperature

sensor - 5. Power - 6. Ground - 7. Reference voltage -

8. Output signal.

The heated film flow meter is arranged between the turbine
and the intercooler.
The suction air temperature sensor is built into the flow
meter; the flow meter is connected to the ECU pins
A5/A17/A18/A26/A28.
Operation
The hot film membrane temperature is kept constant
(approximately 120

°C higher than suction air temperature)

by a heating resistor.
The air mass crossing the duct tends to subtract heat from
the membrane. Consequently more current is required
through the resistor to keep the temperature constant.
Current uptake is proportional to the mass of air flowing into
the engine. It is measured by a Wheatstone bridge and the
resulting signal is sent to the ECU.

EXHAUST GAS COOLING

A. Intake exhaust gas — B. Cooled exhaust gas — C. Coolant to heater — D. Gas from E.G.R. valve —

E. Coolant arriving from cylinder head.

86036

Cooled exhaust
gas

Coolant to heater

Gas from E.G.R. valve

Coolant arriving
from cylinder
head

Figure 242

Figure 243

F1A ENGINE

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Base - May 2004

Figure 244

HIGH-PRESSURE ELECTRONIC INJECTION SYSTEM COMPONENTS LAYOUT

1 Timing phase sensor — 2 Electro-injectors — 3 Glow plug — 4 Coolant temperature sensor — 5 Electromagnetic fan — 6 E.G.R. valve modulator (if present) — 7. Engine speed sensor — 8 Compressor

(if present) — 9 High-pressure pump — 10 Pressure regulator— 11 Fuel filter — 12 Fuel temperature sensor — 13 Fuel filter clogging sensor — 14 Electric supply pump — 15 Fuel pre-filter — 16 Fuel tank —

17 Battery — 18 Control unit with atmospheric pressure sensor — 19 Throttle pedal sensor — 20 Clutch pedal sensors — 21 Brake pedal sensors — 22 Fuel check valve — 23 Heater — 24 Air temperature
pressure sensor — 25 Hydraulic accumulator (rail) pressure relief device — 26 Forged version hydraulic accumulator (rail) — 27 Hydraulic accumulator (rail) fuel pressure sensor — 28 Engine rev counter—

29 Tachograph — 30 Starter heater indicator light - 31. Welded version hydraulic accumulator..

In box A, there is shown the variant with welded version hydraulic accumulator.

FUEL SUPPLY
HIGH-PRESSURE ELECTRONIC
INJECTION SYSTEM (MS 6.3 - EDC 16)
General

Common Rail MS6.3 is a high-pressure electronic injection
system for fast diesel engines with direct injection.
Its main features comprise:

high injection pressures available (1600 bar);

these pressures can be modulated between 150 bar up
to the maximum operating pressure of 1600 bar,
irrespective of the speed of rotation and engine load;

capacity to operate at very high speeds (up to 6000
rpm);

injection control precision (injection duration and
advance);

lower consumption;

lower emissions.

The main functions of the system are basically as follows:

checking fuel temperature;

checking engine coolant temperature;

checking amount of fuel injected;

checking idling speed;

cutting off fuel in release phase;

checking cylinder balancing when idling;

checking anti-sawing;

checking smokiness at exhaust on acceleration;

checking exhaust gas recirculation (E.G.R. if present);

checking top speed limit;

checking glow plugs;

checking activation of air-conditioning system (if any);

checking auxiliary fuel pump;

checking position of cylinders;

checking main and pilot injection advance;

checking closed cycle of injection pressure;

checking turbocharging pressure;

self-diagnosis;

connection with immobilizer unit;

checking maximum torque limitation.

The system makes pre-injection (pilot injection) possible
before the TDC with the advantage of decreasing the
derivative of the pressure in the combustion chamber,
lowering the noise level of combustion, which is typical of
direct injection engines.
The control unit checks the amount of fuel injected,
adjusting the line pressure and injection times.
The information the control unit processes to regulate the
amount of fuel to be injected comprises:

engine speed;

coolant temperature;

turbocharging pressure;

air temperature;

intake air quantity;

battery voltage;

diesel pressure;

position of throttle pedal.

88435

high pressure
low pressure

F1A ENGINE

395

AILY

Base - May 2004

F1A ENGINE

AILY

396

Base - May 2004

SYSTEM OPERATION
Self-diagnosis — BLINK CODE

The control unit self-diagnosis system checks the signals from
the sensors, comparing them with the admitted limits (see
relative heading):

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

exhaust

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 (E.G.R. if
present)

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.

Checking top speed limit

Depending on the number of revs, the control unit actuates
two action strategies:

at 4250 rpm it cuts off the fuel, decreasing the
electro-injector opening time;

over 5000 rpm it deactivates the electro-injectors.

Checking regular rotation on acceleration

Regular progression is assured in all conditions by the control
of the pressure regulator and the electro-injector opening
time.

Checking glow plug control unit

The injection control unit, in the phase of:

starting

after-starting

times operation of the glow plugs according to the engine
temperature.

Checking activation of air-conditioning system

The control unit operates the air-conditioning compressor:

switching it on/off when the relative switch is pressed;

momentarily turning it off (approximately 6 sec.) if the
engine coolant reaches the set temperature.

Checking fuel pump

Irrespective of the speed, the control unit:

supplies the auxiliary fuel pump with the key on MAR;

cuts off auxiliary pump supply if the engine is not started
up within a few seconds.

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Base - May 2004

Content .. 102 103 104 105 ..

Iveco Daily. Manual - part 104