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 ...

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 ...

The dashboard of your car provides plenty of useful information while you're driving, from the speed you're traveling at to the amount of gas left in your tank. The check engine light is another ...

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 ...

Drivers who clear a check-engine light only to see it return days or weeks later are not dealing with a glitch. Federal emissions regulations require the onboard diagnostic system to keep running its ...

Modern vehicles are pretty complicated pieces of tech. Apart from emissions and other vital functions, the engine control system relies heavily on several sensors to regulate performance. That is ...

I live in New Jersey, one of the states that mandates inspection for all vehicles newer than 1995. My daily driver, a Jeep Cherokee, happens to be a 1996 model year with an OBD-II sensor, meaning I ...

Forbes contributors publish independent expert analyses and insights. Jim Gorzelany is a veteran automotive journalist. This voice experience is generated by AI. Learn more. This voice experience is ...

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 ...