Air Flow Sensor Potentiometer

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. Install test harness V.A.G. 1501 or equivalent at the air flow sensor plate potentiometer electrical plug. Reconnect the injection harness to the test harness.

3. With the volt/ohm meter connected between terminal 1 and 3 of the test harness switch the ignition "ON".

^ The correct measurement should be 4.35 to 5.35 VDC.

4. With the ignition "OFF", connect the volt/ohm meter between terminals 2 and 3 of the test harness.

Potentiometer Trim Screw Location:

5. Remove the sealing compound at the potentiometer trim screw.
6. Start the engine and run at idle for approx. 2 minutes.

NOTE: The engine must be at normal operating temperature, however, the radiator cooling fan must not be running during this adjustment.

Potentiometer Voltage Chart:

7. Rotate the trim screw as necessary to obtain a voltage reading that falls within the voltage graph parameters. Refer to the measurement obtained in step 3.

8. Seal the trim screw with an appropriate compound.

^ If the potentiometer cannot be adjusted with the trim screw to obtained the correct specification, the air flow sensor assembly (complete) should be replaced.