Air Flow Sensor Plate Position Sensor: Description and Operation

1991 Volkswagen Jetta L4-1984cc 2.0L DOHCSECTION Description and Operation

Air Flow Sensor Plate Potentiometer:





The air-flow sensor plate potentiometer which is located on the air flow sensor housing provides the CIS-E Motronic control unit with information concerning engine load. The potentiometer consists of a wiper brush working on a carbon film.

Potentiometer Voltage Graph:





The E.C.U. provides the air-flow sensor plate potentiometer with a 5 volt reference signal. As air flow increases the sensor plate provides a modified voltage signal back to the E.C.U. via the potentiometer wiper. This input to the E.C.U. is used to control ignition timing, acceleration, and full-throttle enrichment.



RENDER: 1.0x

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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