Winnebago 1987-1989 LeSharo Service Manual page 118

ENGINE FUEL SYSTEM
GENERAL
Closed loop operation occurs when:
• the coolant temperature is greater than 45°C
(113°F), except when the engine is at WOT
• the engine is above idle speed and the coolant
temperature is between 17°C and 45°C (63°F and
113°F)
The cold start injector is controlled by the
thermotime coolant switch.
When the starter motor is engaged, it provides the
fuel enrichment necessary for cold starts.
The supplementary air regulator is controlled by a
bimetallic spring that is heated by the ambient
temperature of the engine and by an electric heater.
The variable amount of supplementary air required
for cold engine operation is supplied by this
regulator. The air bypasses the throttle plate.
The fast idle solenoid, attached to the air bypass unit
near the idle speed adjustment screw, provides an
additional air circuit that compensates for the
decrease in idle speed that results from
A/C
compressor operation.
The fast idle solenoid is also operational when the
starter motor is engaged.
The timer relay energized the fast idle solenoid for
approximately 3 seconds after the starter motor is
de-energized.
C1-3
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A