We've all experienced a check engine light coming on, knowing that unless it's taken care of immediately, it'll be a nagging long-term problem in the back of our minds. It's one of the most important ...

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 we got the invitation to tour Bosch's oxygen sensor plant in Anderson, South Carolina, it had all the allure of eating a sand sandwich. Let's face it, oxygen sensors aren't the most glamorous ...

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 ...