Good afternoon I am having some issues with my ls swap and I'm out of ideas my motor runs but only on 3 cylinders I got good spark good compression injectors 2,4,3,5, and 8 do not get a ground pulse the other three injectors do and all eight injectors have 12v I replaced all 8 injectors I have good fuel pressure I traced all the wire to the pin they are all good firing order is good I got spark to all 8 cylinders what could it be if anybody has an idea please let me know thanks