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 store that showed a code of PO138. They told me this indicates a ...

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 ...

Don't let failing oxygen sensors compromise your engine's performance. O2 sensors are critical to emissions control on your car, SUV or truck. As the name implies, the O2 sensor (also called an ...

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 ...