I noticed my check engine light come on the other day. I went to Autozone to read the codes and these 2 popped up.

P2631 - Front Air/Fuel Radio Sensor (Bank 2, Sensor 1) LABEL Circuit High Voltage
P0404 - Exhaust Gas Recirculation (EGR) Control Circuit Range/Performance Problem

I was driving on the highway this morning to work and the light turned off and has yet to come back on. Any ideas? Could this be a faulty reading or does the Oxygen sensor need to be replaced maybe?

 

could be due to a voltage spike, bad fuel, etc. It could be a faulty sensor or a dirty sensor. I'd honestly run a can of seafoam through the gas tank or vacuum port just to make sure the engine is all good and clean. Wait a few days and see if it comes back. If it doesn't you are good! If it does, about $120 for a new sensor.