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ELECTRONIC FUEL INJECTION - AFC
Auxiliary Air Regulator
The engine requires during the warm-up phase a
richer mixture
.
The increased volume is determined
by the control unit (signal from temperature sensor
II).
The additional volume of air required for this
purpose is regulated by the auxiliary air regulator
and detoured around the throttle valve into the
intake air distributor.
Construction
The auxiliary
air
regulator consists of a slide valve
and a bi-metal spring which is enclosed by an
electrical heating coil.
Operation
If the engine is cold, the auxiliary
air
slide valve
is
fully
open
.
When the ignition switch is turned on
the heating
coil
starts to warm up
.
With increase
in temperature the bi-metal spring becomes weaker
and the slide valve slowly shuts off the air intake
.
Troubleshooting:
Electrical
:
Disconnect the plug to the auxiliary
air regulator. Connect an ohm meter
.
Nominal value
:
approx. 30.
Mechanical
:
Remove hose from the intake manifold
and throttle housing
.
Blow air thru
from one side
.
If the motor is cold
the air must flow freely
.
Switch on
the ignition, continue to blow air thru
and observe that the air flow becomes
restricted with increase in temperature.
.b
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