General Description; Ignition System - Alfa Romeo 33 Workshop Manual

electronic ignition system equipped
with an electronic power module.
system is colfecfed by means of sen-
sors that transform the data into elec-
battery voltage
l
.
position of the accelerator throt-
tle (comoletely closed or open)
system ancl of a~fuel system includes
t h e followirig:!
.
.
a pulsation damper whose task is
to eliminate pulsations due to
pressure peaks
constant pressure difference bet-
ween f,uel system and intake ma-
n i f o l d
an el,ectronic 'power module
a high V~oltage shock generating
D E S C R I P T I O N ' ~ . ~
For electronic injection 1.7 engines'
air intake temperature
.
engine coolant temperature
.
quantity of air taken in by the en-
gine
.
quantity of oxygen present in the
exhaust gases
.
engine r.p.m. (fromsthe distribu-
t o r )
The electronic CU calculates the ope-
ning time of the electroinjectors with
relation to the instantaneous r.p.m.
and load condition of the engine.
Having carried out the calculation, the
CU sees to the opening of the elec-
f o u r e l e c t r o i n j e c t o r s mwhi,ch,
l
owing to pressure gauge, supply ~
a f u e l q u a n t i t y dependent' o n ~
their opening time
an air flow sensor, which measu-
res ait taken in by engine (adju-
sted in relation to air temperatu-
.
supplementary air solenoid valve
suppliyng extra air ,when the en-
gine is cold
a h i g h v o l t a g e d i s t r i b u t o r s u p - ', . electrical iwiring at low and h/gh
plying power to spark plugs
.
four ignition spark plugs
troinjectors for this time. Since the dif-
ference between fuel pressure and air
pressure in the manifold is mantained
constant by a regolator, the quantity
of fuel injected, is proportional to the
delivery time.
Furthemore the injection CU is able to
carry out from~ time to time certain
operations considered necessary un-
der certain engine conditions (e.g.
electroinjector for cold stafl, interrup-
tion of fuel delivery when engine is de-
celerating).
The injection CU also controls the deli-
a switch on accelerator, throttle re-
l
.
an engine Coolant temperature sen-
sor for injection CU
an rpm sensor
.
ding remote control switches and
CU (inserted in air flow sensor)
.
a lambda, probe determining oxy-
gen differences, in exhaust gas,
with respe,ct to thesair (only for mo-
voltage ~
PA 32 790088330 1
. .