How to Troubleshoot a VW Air Flow Sensor

Written by alibaster smith
  • Share
  • Tweet
  • Share
  • Email

Your VW's air flow sensor is an electrical component that calculates the air entering the engine. In doing this, the air flow sensor monitors the airflow for the correct air-to-gasoline ratio. The information gathered by your VW's air flow sensor is gathered in the air intake and sent to the engine control unit (ECU) on your VW. The computer then uses this information to balance and deliver the proper air/fuel ratio to the engine. If your air flow sensor goes bad, you will notice a marked decrease in engine performance. You may have trouble starting your VW or it may stall while you are driving it normally. You'll need to troubleshoot the problem to verify that it is the air flow sensor.

Skill level:
Moderately Easy

Things you need

  • Voltmeter
  • Canned/compressed air

Show MoreHide


  1. 1

    Check the air flow sensor for dirt, dust, or other debris. Make sure that the sensor does not have any particulates on the sensor wires.

  2. 2

    Turn the dial on the voltmeter to the "ohms" setting and measure the resistance between terminals THA and E2. You will need your specific VW service manual to locate the exact location of these terminals. Touch one lead on the voltmeter to the THA terminal on the air flow sensor, and touch the other lead to the E2 terminal on the sensor. The reading should be at or near 0 but a variance of +/- ".05" is acceptable. If the resistance is outside of this range, then your air flow sensor needs to be replaced.

  3. 3

    Set the dial on the voltmeter to "volts." Touch the positive lead on the voltmeter to the VG terminal, and then touch the negative lead on the voltmeter to the E2G terminal. Check the readout on your voltmeter; it should show no voltage.

  4. 4

    Blow on the sensor wires or use a can of compressed air from a few feet away to gently move air across the sensor wires on the bottom of your VW's air flow sensor. The voltage should fluctuate. If it does not, then your sensor is faulty and needs to be replaced.

Tips and warnings

  • For specific information about your VW vehicle's air flow sensor, consult the particular vehicle's manual (see Resources).

Don't Miss

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the site, you consent to the use of cookies. For more information, please see our Cookie policy.