Question2007 Elantra, about 35k miles, engine light came on, code P2251 according to local repair shop, which i think (via google) is the O2 sensor. How freaked out should I be? Is it drivable?
AnswerThis is a minor issue and may cause a drop in fuel economy. That'll probably be all you can detect beyond the check engine lamp.
The code indicates that there's an open in the reference ground circuit, but I've never seen this occur that it wasn't in the oxygen sensor itself.
This is still a warrantable issue on your vehicle, since it's still within the 5 year/60,000 mile basic warranty period. If you haven't already done so, take the car to your local dealer for repair.
