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Air Flow Sensor Potentiometer

Fig. 12 Air Flow Sensor Potentiometer Schematic:




Fig. 13 AirFlow Sensor plate Angle/Voltage Graph:






The air flow sensor plate assembly uses a potentiometer to measure the position of the sensor plate. The potentiometer is mounted on the side of the air flow sensor housing, under the fuel distributor.
The potentiometer consists of a wiper brush rubbing on a carbon film, Fig. 12. It sends a variable voltage signal to the control unit based on sensor plate position, Fig. 13. The signal is used by the injection control unit for cold acceleration enrichment, and by the ignition control unit to determine engine load (taking the place of the vacuum line used on earlier CIS-E systems).