Could it be leaking injectors or PCM glitch? Can it be related to upstream O2 sensors as well? Where should I look?
The truck runs just fine, no rough, no stalling...
The only number that I was able to understand was vehicle speed 3mph and 1600 rpms

 

Here's another update-
Since yesterday I couldn't find my meter I was using the voltage info from the SBB box. Today I checked the voltage straight on the battery, with the car off it was 12-12.3V and with engine running 14.4-14.6V, revving would go to 14.8-14.9V. So I assume the battery is good even if it's a Walmart battery with the sticker saying mfg date 12/18.
When I plugged the scanner this morning it was showing green light, no pending codes. Two restarts later check engine codes and light.
Here are the pics of live data
Gone to read what those numbers mean...

 

I find it interesting that on bank one sensor 2, voltage is .195, and fuel trim is shown as N/A, but, on bank 2 voltage is .745 and fuel trim is 99.2???? WTF? Sensor 2 are post cat, and should have very little, if ANY effect on fuel trims...... Are those values constantly changing??

 

Tried two more times, the numbers are pretty much the same. On revving to 2000 RPMs the long fuel trim goes down to 27-28 from 32. This is the latest, on idle, hot engine after about 10 miles drive home. I also have another advanced code reader but wouldn't connect to engine or PCM, only transmission, AC, ABS, airbags.
I ordered the upstream O2 sensors, does it make sense to order the downstream as well? Or better to check connections from downstream O2 sensors plugs to the PCM?
Got the Fel Pro exhaust manifold gasket, will take care of broken exhaust studs this weekend. Doesn't sound hissing on cold, but maybe there's a leak given broken studs...

 

I could try to swap sides of downstream sensors to see if there's any changes before ordering them- it's almost hundred bucks...

 

NTK or Denso O2 sensors only please. Rock Auto has pretty good prices on them, and my local advance auto will price match Rock Auto....

Try swapping them, and see if anything changes. Might try simply unplugging them, and see if it runs any better as well.

 

The old sensors are NGK/ NTK so I've got NTK from Amazon, $45 for both upstream, O'Reilly guys were selling me Bosch for $36 each claiming that's the right part. Cross checked the part numbers on rockauto. Had some bad experience with chinese brands before on other Dodges of mine, they not only don't work, but trigger up to ten additional codes.
By the way, the mpg is about 9-10 on city cicle, is that allright? My coworker's got a 2003 RAM HEMI and he says that's normal

 

Probably pretty close. Fuel mileage will decrease in winter months, simply due to using winter blend gasoline...... (assuming you live somewhere that winter is an issue. ) In all reality though, I think it should be able to do a bit better than that.

 

No, it's not an issue really, it's sunny California)))
​​​We barely got two frosty mornings past month)
Yesterday ordered as well the Haynes repair manual, maybe will find some answers.

 

Bah. I live in michigan.... though, today, winter doesn't seem to be all that much of an issue.

haynes manual is not really as helpful as you would like. Get a REAL factory service manual. I think they are published by Bishko? They ain't cheap, but, the information is accurate, and there is a LOT of it. Including accurate wiring diagrams, and troubleshooting steps.