i am working on a 2009 gmc sierra 1500 4x4 5.3 6l80e and thee oil pump when out and i put a used engine in it it with a new oil pump and i had a misfire and lean codes and i replaced the intake manifold gaskets and i thought that fixed it and i had driven it 80mi and was about to give it back i the check engine light comes on and it has a hiccup everonece in a while but only when accelerating at low speeds has new plugs, wires, i have swaped coils from the old engine that worked, o2 sensors all 4 im at a loss of what to do next. so any help would be greatly appreciated thanks.


here are the codes

https://usait.x431.com/Home/Report/r...type/D/l/en-us

 

Sometimes your injectors will hang open causing codes related to this. With whatever cylinder is misfiring, I would see if your injector is hanging open.