Low fuel consumption

Welcome to 2CarPros.

The oxygen sensors on vehicles signal the computer as to how rich or lean the engine is running. With that information, the computer adjusts the air / fuel mixture. If there is a fault with one of the sensors, the computer will run the vehicle in what is called a closed loop. Under those conditions, the computer will provide a rich fuel mixture to ensure the engine runs, thus using more fuel.

Here are three links for you to review. The first describes the purpose of the O2 sensor. The second link explains how to test one and the last explains how to replace one. Take a look through them. This is most likely something you can take care of yourself and save money.

https://www.2carpros.com/articles/how-an-oxygen-sensor-works

https://www.2carpros.com/articles/how-to-test-an-oxygen-sensor-02-sensor

https://www.2carpros.com/articles/how-to-replace-an-oxygen-sensor

If you decide to test the sensor, you will need a volt meter or multi meter. Here are two links explaining how to check wiring and how to use a volt / multi meter:

https://www.2carpros.com/articles/how-to-use-a-voltmeter

https://www.2carpros.com/articles/how-to-check-wiring

Let me know if this helps you or if you have other questions.

Take care,
Joe