Well here's an update. Unhook top pump take belt off noise goes away . install belt back on hook back up knock comes back...unhook Lift pump noise goes away. Idles fine for more than 30 seconds. Reflash ecm to previous stock injector file start truck no noise. Reinstall 100 over tune start truck immediately says reduced power upon key turn starts up pump knocks u hook lift pump truck acts as if it's going to die....tech 2 go command rail nothing happens....clear dtc go command rail 13k is all you can get. At idle rail won't meet desired. Rail plug is tight as a dickens in there with an impact . at this point I'm blaming the controller. I rewired the leads for it on the battery just to say I did. Truck doesn't want to run right acting like it wants to stall and buck with the lift pump on and working now. Reduced engine power every key on. Drives ok otherwise. What else could it be besides this Damn controller ??
My thoughts;
First, I'd load the proper injector calibrations into the ecm.
Second, I'd remove the belt and remove the controller, hooking up the factory cp3 harness to the valley pump and test. With the lift pump on and the 100% inj tune. Then do the same test with the stock injector tune. Which ever tune works, then connect the controller and cp3 and see if there problem is still there.
Lift pump pressure at or below 15psi should not cause an issue on a LBZ/LMM. I run 40psi on my LBZ race truck and I ran 15psi on my street truck for years.