Hi everybody.I have a 2000 GMC 3500,crew,4x4,with a 7.4.I blew my motor and replaced it with a 99 454 out of an identical truck using my electronics.When I started it up it will only run on the passenger side.I checked all the connections and everywhere.Any Ideas??? I so need it to run for work.Thanks for any help.Lonnie 904-418-2376

 

You could have pinched a wire going to the drivers side injectors. It is not hard to do. I would pull the upper intake and check the wiring very closely. There isn't much space back there where the harness exits with the fuel rail, intake, and distributor so close. The harness needs to exit on the bottom of the fuel rail. Also make sure the clips are holding the harness to the fuel rail. I added a couple zip ties on mine. Good luck!

 

Also check the big plug that runs the injectors and make sure there isn't any damaged or bent over tabs in there.