Ok, so here we go:
Brand new batteries
Cleaned fuel bowl, new fuel filter
Cleaned the IPR
It will start cold, but not warm, unless I hit it with the smallest amount of ether (after disconnecting the plugs, of course).
When it's warm, I'm getting about 160psi from the HPOP until it turns over about 10-12 times. Then it will work it's self to 2465 - but no start.
I've got a code 1212 and 1211 still (even after cleaning the IPR), and P0470 (back pressure sensor malfunction).
I've got 16% oil return KOEO, warm crank to start: 25%, Full load 46%
I can start the truck fine when it's cold, and it runs like a mother. When it gets to operating temp, it's like it's not getting that initial burst of fuel to get it to catch. Any ideas? I'm about to pull my hair out and drive it off of a cliff (as long it's a cold start!

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