Air Flow Sensor Plate Position Sensor: Testing and Inspection

Air Flow Sensor Plate Potentiometer Location:

1. With the ignition "OFF" detach the air flow sensor potentiometer harness connector.

Air Flow Sensor Plate Test Connection:

2. If available connect test harness VW 1501 to the potentiometer plug and measure the resistance between terminals 1 and 2. Do not reconnect the harness connector.

Air Flow Sensor Plate Potentiometer Adjustment:

If test harness VW 1501 is not available connect a suitable volt/ohm meter between terminals 1 and 2 of the potentiometer plug.

^ The correct measurement should be greater than 4000 ohms.

3. Connect the volt/ohm meter between terminals 2 and 3.

^ The correct measurement should be less than 1000 ohms.


4. Remove the intake air boot at the air flow sensor.
5. Measure the resistance between terminals 2 and 3 of the potentiometer while lifting the sensor plate slowly and evenly.

^ The resistance should steadily increase to over 4000 ohms without any flat spots.

If the correct results are not obtained, replace the air flow sensor potentiometer.