You kinda beat me to where I was going. I don't know about resetting it or replacing it will fix it, but definitely believe it's the flex fuel sensor..Check the fuel trim for ethanol percentage, my 08 avalanche had a reading of 63 percent, I reset it to 3 percent, clear codes all is good. I had this happen before, even with trucks that don't burn ethanol and it will trip o2 issues. I reset it with my tech2 scanner.
I think your right...Those combo of codes just screamed flex fuel sensor to me.. but I'm just a guy on a phone typing nonsense part of the time. lolI have new 02 sensors...new MAF....new MAP sensor...I think it has to be something on the front end sending wrong info to make the fuel level rich on both banks..so it could be flex sensor
If it is the flex fuel sensor, I just don't know if it's something that can be reset at a shop or has to be replaced. That's where my experience hits a wall. Curious to find the end result though..Maybe one of the other members can take this diagnosis further.I'm just a guy begging for answers don't mind me
I understand the word diagnosis...I also know there has been suggestions made and nothing but chit chat has happened.....I don't think you understand what the word "diagnosis" means. So far, no diagnosis has happened on this thread. It has been suggested multiple times, but none has actually happened.