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 ...

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 ...

We earn commissions from purchases you make using links in our articles. Learn more. If your car experiences poor fuel economy, lacks power, feels sluggish, idles rough, or has an illuminated check ...

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 ...