How to Replace a Mass Air Flow Sensor in a Chevrolet

Engines are combustible and need air in order to run properly. Cold air is denser and has more oxygen so it is more beneficial for the engine. When a mass air flow sensor goes bad in your Chevrolet, the check engine or service engine light will come on. You may experience poor performance issues with the engine. The mass air flow sensor calibrates changes that occur with the intake air flow as well as fuel and spark timing. Although it sounds complicated and is expensive to replace, it is relatively easy to install in your Chevy. Save yourself some money on labor charges and pop it in yourself and while you're there, it would be a good time to consider replacing your air filter if you haven't in a while.

Things You'll Need

  • Phillips head screwdriver
  • Open the hood to your Chevrolet with the engine off.

  • Locate the engine air filter box. The model of Chevrolet and size motor you have will dictate the location of the air box. Refer to the owner's manual if you need assistance finding it.

  • Follow the black air tube that runs from the air box to the throttle body. Located about in the middle of the air tube (on most models) is a small square metallic looking device with an electrical outlet plugged into it. That's the mass air flow sensor. Take the new one out of the box and compare how it is supposed to seat inside the air tube. Be care not to touch the internal element of the new sensor.

  • Unplug the wire outlet in the mass air flow sensor.

  • Loosen the air tube band clamps using the screwdriver. It might be easier to remove the tube connection from the air box and the throttle body and remove the tube as an assembled unit even though there are band clamps on either side of the mass air flow sensor. If a vacuum line tube is inserted into the air tube, you can simply pull it out. Remove the air tube.

  • Loosen the band clamp on one side of the mass air flow sensor and remove the tube. Insert the new mass air flow sensor and tighten the clamp. Repeat for the other side of the air tube.

  • Reinsert the air tube into place. Be sure there are no loose connection and the tube is securely covering the air box and throttle body connections. Tighten the clamps. Plug in the vacuum line if there was one you had to unplug. Plug the outlet back into the mass air flow sensor. It would also be recommended to open the air box and replace the air filter if it hasn't been done in a while.