The "Check Engine" light is the most feared dashboard notification, but for the Oxygen (O2) sensor, it is a lagging indicator ...

When the check-engine light snaps on, it is not a suggestion, it is your car’s way of saying something in the powertrain or emissions system needs attention. I see it as an early warning system that ...

Why Replace A Faulty Oxygen Sensor? A faulty sensor cannot transmit accurate data to the car's computer, causing the engine to run unbalanced. An unbalanced engine either burns fuel with too much or ...

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 ...

Add Yahoo as a preferred source to see more of our stories on Google. The check engine light can turn on for a wide range of reasons. Sure, a loose gas cap is usually the best case scenario, but you ...

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 ...