Hello all so I have been doing a lot of reading and trouble shooting, still no solutions. My truck is defueling itself at 1900 rpm then comes back to 1900rpm  sometimes even revs up at 1900 no idea why not throwing any codes . My sensors are buzzing all over the place reading high . Here is what I’ve done. Checked vss and neutral ground,New cam sensor , disconnected pcm to just run on Ecm  still problem is there . Then I tested my map sensor with ohms to ecm checks out fine  checked apps checks out fine .  I’m now thinking ground problem I checked them all and double checked. I was just messing around with ohms and tested my 5v on map to  my double connector , the one that splits to fuse box and pcm.  I got a weird resistance of .5 from map 5v pin to a solid orange wire in the white locking double connector. I then traced that back to the ecm pin #46 witch from your wiring diagram is the crank sensor sending wire. The only time I get this reading is with the ecm wiring plugged into the ecm, when unplugged I have no ohms at all ? I then thought I would check my oil sending unit beings it shares a 5v wire with map . I do not have a oil sending unit it would appear ... there is a sensor below the ecm but it only has one wire gry/Black I will try to attach pictures it goes to pin#26??? Witch makes no sense because that is the pto pin according to your schematics ?? And on top of it pin # 6 which is where the oil pressure sending wire should go is empty ? Why would this be? I am about to buy a new engine harness and ecm  I just don’t want to spend the money if it is not the problem?  I’m sure I am missing more but just can’t remember at this point . I am in great need of everyone’s expertise!  And I just wanted to say I am very grateful for all of the info everyone has contributed to this site wouldn’t have got this far without it. oh and fuel pressure is good never drops below 11

Good to hear