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

While relatively minor, check engine light repairs can be costly if neglected, leading to as much as 40 percent lower fuel efficiency. Metro News Service photo While relatively minor, check engine ...

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 ...