Airflow Meter; Throttle Plate & Throttle Position - Winnebago 1987-1989 LeSharo Service Manual

ENGINE FUEL SYSTEM
AIRFLOW METER, THROTTLE PLATE & THROTTLE POSITION
The sensor flap has a rubber damper to protect the
sensor from any damage during back pressure peaks.
An air temperature sensor (22) is located in the air
0
flow.
In the L-Jetronic system, all injectors are controlled as
one single group.
This method has the advantage of simplifying the
system considerably. However, in order to ensure
even fuel distribution, two injections occur for each
rotation of the camshaft. Each injection contains half
the amount of fuel required for one complete engine
cycle.
AIR FLOW METER
The function of the airflow meter is to supply a
voltage signal that varies with the amount of air
drawn in by the engine.
This air pushes against a movable sensor flap.
In response to the incoming airflow and the
opposing action of a spring, the flap is moved into an
angled position that is transmitted to a
potentiometer.
A compensation flap is attached to the sensor flap. It
has the same active surface area as the sensor flap, so
it compensates for pulsations resulting from any
possible back pressures. This keeps back pressure
from affecting airflow measurement.
THROTTLE PLATE AND THROTTLE POSITION SWITCH
In order to control the amount of air admitted to the
engine, a double throttle plate assembly with
delayed throttle plate opening is located after the
airflow meter.
A switch is attached to the throttle plate shaft with
one contact for idling and one contact for full
throttle. The control contact closes the idling contact
or the full throttle contact for a given air throttle
plate position. The control unit analyzes the output
signals to calculate the length of injection time.
2
1 - Integrator voltage adjustment screw
2 - Sensor flap
5 - Electrical connections
6 - Damping chamber
7 - Compensation flap
22 - Air temperature sensor
1 - Idling contact
2 - Full throttle contact
C2-4