Fiat Bravo Service Manual page 156

Bravo-Brava
Cut-off
The fuel cut-off strategy is activated when the E C U recognises that the throttle is in closed position
(throttle potentiometer signal) and engine speed exceeds 2000 rpm. The E C U activates cut-off only
when engine temperature exceeds 0° C.
The fuel supply is restored when the throttle is no longer closed.
R p m .
~ 1 6 0 0 R p m .
~ 1 4 0 0 R p m .
Acceleration
During this stage, the ECU increases the amount of fuel required by the engine (to achieve maximum
torque) on the basis of signals from the following sensors:
- throttle potentiometer;
The base pulse constant is multiplied by a factor according to coolant temperature and accelerator throt-
tle opening speed.
If an abrupt change in injection time is calculated when the injector is already closed, the ECU reopens
the injector (extra pulse), in order to make the concentration up to the required level as quickly as possi-
ble. Subsequent injections are automatically increased as described previously.
Copyright Fiat Auto
^
16v
- absolute pressure sensor;
Fuel system
A. entering
80°C
B. leaving
T E M P . H 2 0
- rpm and T D C sensor.
A. normal
tion time
B. injector
re-opening
(extra pulse)
C. injection time
including en-
richment
OFF. engine
ON. engine under
P4A07CJ02
Engine
10.
cut-off
cut-off
injec-
under
steady-state
conditions
transient con-
ditions
1