Hi all, I have been handed a 97 DeVille with a fresh junk yard engine transplant,it sets misfire codes for #7 and B1S2 o2, I see it has a new ac delco o2 in this spot,now watching fuel trims LTFT 1 is running at idle -11.7 to -13-2% and LTFT 2 is +35.2%,now wa... Login to read more.