Eric.. You can't mix parts of different harnesses you need a complete harness for a 4.0 from a single vehicle. Is that connector attached to the 4.0 or is it part of the original harness for the 2.9

 

The computer and the harness or for a 4.0 the only thing that I needed was the injector harness and the camshaft sensor harness I was told I can just splice my old one into the new one

 

Can't figure out the problem, one day as I was driving my battery light came on but every thing seemed fine untill that night I turned on my lights and battery went dead in a few minutes.So the next morning I changed my alternator l checked my battery it was bad so I changed it also I thought my problem was solved but still not working I realy need your help