So far I have replaced the fuel pump, fuel filter, injector assembly, O2 sensors,
I'm correct to assume you had the problem before replacing all of these parts? It's been a minute or 2 since I've worked on one of these. IIRC there used to be a BUNCH of wrong fuel pumps out there. (This is an "R" motor isn't it? 8th vin digit = R) The injectors were problematic, but usually caused cold starting, or cold skipping/misfire problems.(It's the spider looking injector assembly under the intake isn't it?) If you unplug all the O2 sensors how does it run? Does in run like it needs more fuel, or does it run OK. (this forces open loop) Again if I'm remembering these models correctly I've seen PCV problems cause lean codes. Make sure there's a good connection from the valve cover to the air cleaner housing. Timing chain, or distributor gear problems usually cause low power or detonation. If the cam to crank angle is off enough it will set DTC's. You can see the cam to crank angle with a scanner, but I don't remember what's it's called. I've slotted the distributor hold down to get a few more miles out of ones with worn timing chains. I've had driveability problems caused by (what I call) tuliped intake valves. The cranking compression would be good for some reason. I don't specifically remember lead codes...but it's been a while. Connect a vacuum gauge and see if it dances around at idle.
I used to work on these pretty much every day a couple decades ago. I apologize for not remembering more, or if I'm remembering the wrong engine.
I used to be a people person, but people ruined it.