jaramart

Hi all, i have been hunting a problem on my ML320 2000 V6.
History:
Driving around fine one day, i hope out leave the car idling for no more then 3mins. When i return the car is rough idle misfiring. I turn the car off and starts it instantly and the problem doesn't appear again?
drive the car for the rest of the day no problems at all. Next morning i go down to the shops the car starts and drive fine. then on the way home i notice a lack of power, hesitant to change gear, it got so bad i didn't think i would make it home.

park it in the driveway and grab my scan tool and reads a myriad of trouble codes. so the fun begins, as per codes all four O2 sensors where faulty which had to be done anyways as the truck has 230K on original O2 sensors.

i should also note that the truck has started to develop a long crank time and struggles to start.

next is MAP sensor, replaced that
i did all the plugs and noticed that two coil packs have failed. so replace all coil packs.

i also replaced the MAF too

Now i no longer get error codes when i scan however i still have a problem, that is when under load the car struggles to rev out. So i replace the fuel filter needed to be done anyways.

ok so today i start the truck which still take 10 or more seconds of crank on the first go, and it idles ok, but it seems to backfire if i give to much throttle at idle to quickly. so i let idle for a good 15-20mins to get to operating temp. Now it misfiring on all cylinders and eventually stalls
i grab the scan tool and get the following codes

2050-001
2050-032
2050-064
2051-001
2051-032
2051-064
2043-001
2043-016
2043-064
2044-001
2044-016
2044-064
2045-001
2045-016
2045-064
2048-001
2048-016
2048-064
2046-001
2046-016
2046-064
P2006-002
P2006-016
P178300

what am i missing? i think it has to do with fuel/delivery as i have done all ignition side of things