ENGINE 1.3L QUADRAJET (90PS)
115
I. CONTROL OF AMOUNT OF FUEL INJECTED
On the basis of the signals coming from the sensors
and the values stored, the control unit :
Q
controls the pressure regulator on the rail;
Q
controls the regulator on the pressure pump to
modulate the fuel flow rate (for the 90 CV version
only)
Q
varies the "pilot" injection time in the entire rpm
range;
Q
alters the "main" injection time.
J. IDLE SPEED CHECK
The control unit processes the signals coming
from the sensors and regulates the quantity of
fuel injected:
Q
controls the pressure regulator;
Q
alters the injector injection times.
Within certain limits the speed takes the battery
voltage into account.
K. FUEL CUT-OFF DURING DECELERATION
During the accelerator pedal release stage, the
control unit implements the following logics :
Q
places the injector opening time at zero;
Q
partly varies the injection time for the injectors
before the idle speed is reached;
Q
controls the fuel pressure regulator.
L. IDLE CYLINDER BALANCE CHECK
According to the signals received from the
sensors, the control unit controls the idle speed
torque :
Q
alters the quantity of fuel injected by the individual
injectors (injection time).
M. CHECK ON IRREGULAR OPERATION
The control unit processes the signals received
by the various sensors and corrects the quantity
of fuel to inject in order to improve driveability
reducing shuddering whilst driving by means of
the injector opening time.
N. EXHAUST FUMES CONTROL DURING
ACCELERATION
In order to restrict the fumes during fast
transitions, on the basis of the signals received
from the accelerator pedal potentiometer, Lambda
sensor, flowmeter and the engine speed the control
unit limits the amount of fuel to be injected by
means of :
Q
the pressure regulator
Q
the injection time for the injectors.
Q
E.G.R.
O. EXHAUST GAS RECIRCULATION CONTROL
(E.G.R.)
In accordance with EURO 4 pollution control
legislation, on the basis of the engine load and
the signal from the accelerator pedal
potentiometer, the control unit limits the quantity
of intake air, implementing the partial intake of
exhaust gases, through :
Q
the adjustment of the opening of the E.G.R. valve
P. MAXIMUM TORQUE LIMIT CONTROL
According to the rpm level, the control unit
calculates the following in pre-defined maps :
Q
the torque limit;
Q
the permitted fumes (limit).
It compares this minimum values and corrects
them with other parameters :
Q
coolant temperature;
Q
engine rpm;
Q
vehicle speed;
Q
air temperature.
and controls the quantity of fuel to be injected
(pressure regulator - injectors).
Q. MAXIMUM SPEED LIMIT CONTROL
When the engine speed reaches 5200 rpm, the
control unit interrupts the operation of the injectors
and the supply pressure is consequently reduced.
R. HEATER PLUGS CHECK
The injection unit, during the following stages :
Q
starting;
Q
post-starting;
Q
applies a timer to the glow plug preheating control
unit based on engine temperature.
