I'm trying to nail this down but unfortunately without any success. Jeep has around 27-9 psi pressure at rail at idle and vacuum connected. With disconnected vacuum it is around 36psi. I think this is main issue why my fuel trim numbers are 5-8%. Things done so far:
Fuel filter has some 3k miles on it. Bypassed fuel filter and pressure is still the same.
Cleaned and tested fuel injectors. All tested good.
Checked vacuum lines
Fuel tank had to be dropped for skid replacement, so I replaced fuel pump at the same time /w new strainer
Replaced fuel pressure regulator