2003 F150 2wd, 4.2L V6. I forgot to mention pcodes 1151 and 1131 are both "manufactuer control fuel air metering". 1151 is ecm couldn't adjust fuel trim because of lean or rich condition. 1131 is ECM detected bank 1 02 at its lean condition. And like I said, now my engine stumbles at acceleration from stop, and I'm getting a misfire in cylinder 2 in the 1st 1000 rev.