v8 5.3

Hey guys I just cant seem to find the solution to my problem. I have a 2006 colorado that had a 3.5 in it that I have swaped to a 5.3 I did the harness my self as well as the exhaust and other misc stuff. The 5.3 is. 99 as well as the pcm that I had programmed, I have a couple issues but the...