Recently purchased the truck. Shows 133,*** on the odometer. Got truck with a K&N filter and a straight through 4" muffler. Still has cats. In the process of replacing leaking intake gaskets and repairing a hard hot starting issue, I did a new fuel pressure regulator, 5.0 motorsports "stock improvement injectors," cap, rotor, upstream 02's and fuel filter. Put 100 miles on it today and got CEL for lean on both banks. Pulled up fuel trims and went for a drive, both long terms at at 25. Checked for vacuum leaks, cant find any with ear or carb spray. Checked fuel pressure Key on engine off, cycled 5 or 6 times got 52 psi. Running pressure is 45 with a spike up to 50 when I whack the throttle, no load. Pinched off the return line briefly and had no change in psi. Pump has always been loud. Plan is to check engine with a vacuum gauge tommorow, voltage and ground at pump harness, inspect pump connectors if I can get to them, and see if I can get the low amp probe from my scope on the harness without dropping the tank. Truck starts fine when hot or cold, seems little low on power as compared to before. My thoughts are, Old injectors were sticking open, made good power with a weak pump because of that. New injectors want more fuel than the old pump can provide whether that be mechanical or electrical. Probably only put 100 miles on the truck before starting the surgery, so don't have much baseline. Am I missing something?