I have installed a 2015 tahoe engine mated to a 2008 6L90E from a silverado. I have tried to get this thing to run for a while now. I have played with VATS, Stater relay, Fuel pressure sensor and forget what else. I have never seen the injectors be activated or commanded ON at any point of this process. I have had to take a break from it out of frustration. Can it be that the T43 needs to be reprogrammed for a 2015 Tahoe? Or if there are any other ideas that people may have on this it could be helpful.

Thank you