Fast Idle Management; Exhaust Gas Recirculation Control; Glow Plug Pre/Post Heating Management - Fiat Bravo Service Manual

Bravo-Brava 1 0 ™
I
Coolant
temperature
Air temperature
ECU
R p m
Air conditioner
Coolant
temperature
Accelerator lever
position
ECU
R p m
Intake air
quantity
Atmospher-
pressure
R p m
Coolant
temperature
ECU
Air temperature
Accelerator lever
position
Battery voltage
Copyright Fiat Auto
I
Solenoid
fast
idle
Borg
Warner
Solenoid
ic
Glow plug
preheating
control
unit
I F A S T I D L E MANAGEMENT
The control unit activates the fast idle w h e n
at least one of the following conditions oc-
curs:
1. Intake air temperature less than 25° C and
coolant temperature less than 55° C.
2. Air conditioner compressor on.
3. Engine speed less than 750 rpm.
E X H A U S T GAS R E C I R C U L A T I O N
T R O L
The control unit calculates the w e i g h t ratio
between "clean" air taken in and the quantity
of burnt gases which may be returned to the
intake. On the basis of engine load, coolant
temperature and intake air quantity, the c o n -
trol unit controls the Borg Warner modulator
valve w h i c h in turn activates the EGR valve
via a vacuum signal in order to recirculate the
exhaust gas.
GLOW P L U G P R E / P O S T H E A T I N G MAN-
A G E M E N T
The electronic control unit (ECU) controls
the glow plug preheating control unit directly
to manage pre and post heating times, mainly
on the basis of coolant and intake air temper-
ature. When calculating post-heating times,
the control unit also takes into account accel-
erator lever positin and rpm. Heating times
are reduced when there is a high demand for
engine power.
Engine
Fuel system
10.
C O N -
9