2000 s80 2.9L idle and fuel trim issues

[rigozzi]

Need some advise on the next step with my 2000 s80 2.9. I recently picked up this car for just about free. Of course it had no service records but a VIN search showed no major accidents (reported of course) and that the ETM had been replaced under the recall. It had some brake issues but thanks to the forum I was able to repair the ABS module successfully restoring brakes and resolving brake issues. So I started attacking codes. To date I have replaced the following components:
ETM with pre programmed xemodex unit
MAF sensor (Bosch)
Crank Sensor
Fuel injector seals
Fuel filter
ECT sensor and Thermostat
IAT switch/sensor (on air-box)
All vacuum lines in the engine compartment
Spark plugs and coils (Volvo)
All 4 o2 sensors (Bosch)
Oil trap (and hoses)
CVVT Solenoid
Intake/phlenughm gaskets
Cat/exhaust flange gasket
Engine management relay
So after replacing all these parts I'm still having the same issue and it is about to cost me my sanity. After a hard reset the car will either a) start and idle high for 5-10 seconds and then settle and purr like a kitten until warm or b) run like dog poop before stalling and then repeat 2-3 times before achieving a terrible idle. In scenario "a" once the car reaches operating temp, it starts to act as if it is in a misfire condition shaking and sputtering in what I call a "machine gun" idle. If I engage the accelerator the engine will smooth out only to return to machine gun idle. When attempting to drive the car, it will accelerate decent but almost always"bog down" around 2000 rpms sometimes clearing up but sometimes I have to let off accelerator until rpms reach idle and then normal acceleration will return until it bogs down again. The most frustrating part is that it will not tgrow any codes, orcat least codes that I can pull with my scanner but I know it is faulting bc if I clear the codes while accelerating, I can notice an extreme difference in performance, momentarily, but no codes are being shown on scanner. The live data is showing what should be considered acceptable fuel trim data with the exception of B2S2 consistently reading N/A. The other strange thing on the live data is the IAT reading reads, and always has, -40°F. Every so often it will generate codes : P0134, P0154, and P1171 which are all o2 sensor and ETM related codes. I have inspected all the wiring between o2 harnesses and ECU and metered them out with no opens and no shorts showing. One thing, when I replaced exhaust flange gasket I noted the catalytic converter has been gutted. Is it possible that the absence of the catalyst is causing the front and rear o2 sensors to have the exact same readings in turn throwing off the ecu and causing bunk fuel trim and throwing 134 and 154 codes? Also an occasional P0171 code. I have been working on cars for 25 years and Volvos for about 5 and this is hands down the most frustrating troubleshoot of my life. Any insight will be greatly appreciated. Additionally, fuel pressure and compression checks are flawless on all cylinders. ETM update from dealer? Fuel pressure damper? Injectors? Thanks guys.