Clear the codes with a scan tool (disconnecting battery doesn't cut it). Then if a code resets and the light comes back on, post the code number. 13-14 mpg is normal for around town fuel mileage on a 4WD Blazer.

 

I been having this same issue but my code read it was running lean, I replaced my fuel pump and filter and cleaned out gas tank, the light went off today while the wife had it out and so far it hasn't came back on but well see lol. I also cleaned the mass air flow senor with cleaner. I'm still having my hesitation issue but I'm sure I can soon figure that out as I have all my other issue. wish you the best of luck on getting it fixed if you haven't already.