LS1 question. Old truck has a 2000 Yukon LS1 ECM (I think) I get all kinds of trannie & torque converter errors. It has a freestanding trannie controller so I really don't need the ECM to talk to the trannie. Can I turn that part off? Or do I need a new program?

Also, when I get moderately on the throttle, it acts like it is about to shift down, retarding the timing maybe, runs rough like as if it were on 4 cylinders and won't run properly until I shut it off and the restart it. I bought it this way and do not know what programmer he used.

Anyone have any thoughts on this?