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ELECTRONIC FUEL INJECTION - AFC
Fuel Injector
The
volume
of injected
fuel
is determined
by the
length
of
time the injector is
open
(i.
e. the time of
the impulse from the
control
unit).
The
injector
is
connected
to
+
via the resistor (R).
(The contro
l
signal
from the
control
unit is
of
negative
potential.)
Injection Sequence
All
injectors are activated simultaneously, once
for
every
c
rank
shaft
revolution.
Note
:
The
plug and
socket
assembly
is
so arranged that
it
can not
be
inadvertanly
connected to an injector
of
the MPC
injection.
Pressure Regulator
The pressure regulator regulates the pressure of the
fuel
in
the ring
supply
line
independent
of
the
pressure in the vacuum line.
The
spri
ng chamber of the pressu re regu lator is
connected to the intake
air
distributor via
a
hose
.
Operation
By u
s
ing this
configuration
the pressure of
the
fuel
i
s adj
u
sted independent
of
the vacuum in the intake
air distributor.
For
example
Hi
g
h vacuum in
the
intake air distributor (idle
operation) -
low fuel pressure
.
L
ow vacuum
in the
intake
air distributor (full
load) - high
fuel pressure
.
This way, the difference between fuel pressure and
intake air
distributor pressur
e
always remains
the same
for
all
load
conditions
of the
engine.
Troubleshooting
:
Con
n
ect a
pr
essur
e
gauge
into the ring
supply
line. Disconnect
the
vacuum hose from th
e pressure
reg
u
lator.
Start the motor
.
Nom
i
n
a
l
value
:
2
.
5 bar (36.75
psi
approx.)
Reconnect the hose
the fuel pressure must
now
be lower.
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