I just this hour return from my mechanic (non-dealer) and he reports that he's getting a code 31. Apparently this at least in part agrees with your assessment because it mentions in the text that the car is running too lean.
It gets more complicated for me at this point because he then said that he was confused as well because he couldn't clear the code. I hope you know what that means because he tried explaining that he should be able to tell the computer to clear that code and he wasn't able to do that. So I asked what's next? He said that he had to check every code individually and that was a very time consuming processs. That sounded like a code for expensive and had him button it up until I could submit this on this forum. Here it is. Is there any hope?