Oxygen Sensor
 

My service engine soon light came on in my 01 Montero Sport. I took it to the guys at advanced and they told me that it was my Oxygen sensor in Bank2 Sensor1. He also said the best thing to do would be just unplug it and reset it.

I need to get my registration for my car, but here in North Carolina you cant do that unless your car has a current passing inspection. Which it wont pass if the check light is on.

Should I just replace it or reset it? And where is the thing even at?