First start up, on first swap had some troubles

[derotoreut]

So I started my 5.3 LM7 for the first time. This is also my first LS swap. The engine fired right up, but it wasn't without some problems. It seems like it doesn't want to idle too well, but runs OK with some throttle. After a short time running it starts running roughly and wants to die. Then I can't keep it running.

It threw a code P0650, MIL Control, Circuit Malfunction. From what I can tell, it doesn't appear to have anything to do with the way the engine runs. Any thoughts are greatly appreciated.

I don't have a fuel pressure tester, but I do plan to buy one. Once I get it, I'll check to make sure I have good fuel pressure with key on and running.

I ran the issue by my harness builder who thought maybe the problem was from using Dakota Digital's BIM-01-2 OBDII interface module with my RTX gauges. Apparently there have been some poor running problems associated with using this module. I reset the code and this time didn't connect the DD BIM module and it made no difference. Still starts good, but after a short period runs rough and then dies.