Add Yahoo as a preferred source to see more of our stories on Google. Q: In my vehicle, the check engine light comes on and then goes off and it is now back on. I had a test done at local auto-parts ...

Your car's O2 sensor can cause rough running, bad mileage, and inspection nightmares. Can a quick clean save the day? Here's what you need to know.

Oxygen sensors play an important role in your car's engine, but they aren't like many other components, such as oil filters, for which automakers provide a strict service schedule. Instead, the real ...

I had a test done at local auto-parts store that showed a code of PO138. They told me this indicates a problem with the oxygen sensor. I replaced the oxygen sensor and the light never went out. I ...