Problems with starting, acceleration
Your problem is with the lean AFR after start up. It is WAY too lean. The computer is trying to compensate and is maxing out the fuel learn. It can't give it any more fuel and it is still showing lean. That is why I think you have a misfire on 1 or more cylinders. A misfire will show up as a lean condition on the AFR.
Do you notice when it is running bad if there is black smoke from the exhaust or a very rich smelling exhaust. Does the exhaust fumes make your eyes water?
There is no smoke. I don’t think it smells rich. I think it’s not getting fuel. Acts like a carb with a float stuck closed. Which I experienced with my old engine and carb.
It could be that it is a fuel delivery problem.
What are you running for a fuel system and fuel pump?
What type of fuel lines fittings and filters?
Is there any restrictions in the fuel lines?
Are you able to measure fuel pressure at the throttle body?
I am running the electric fuel pump that came with the fitech kit along with the filters it came with. Fuel lines were replaced. It runs fine after the warm start problem clears. No major issues other than warm start after sitting 30-40 minutes. That is my major complaint right now. No way to check pressure at the unit.
Which electric FiTech pump? An inline pump or the Fuel Command Center?