04 6.0L can't figure out engine issue

[Jrod78]

I read this forum pretty often but never post. Long story short, is I have seen on here and read several people with some of the symtoms my truck is having, but none are quite the same.
2004 truck (03 Engine) 6.0L PSD, Stick shift, 160k miles, All brand new injectors about 20k miles ago. I've been driving this truck since Nov. 04 with very little trouble.
This is what I can tell you. Left for work to get fuel and turned my truck off, which I normally do not do..but my E brake is worn out and it rolls sometimes. Filled up and started it, but it was different sounding instantly..barely started and sounded very muffled like under the hood with little to no throttle response. It sounded like a compact tractor seriously(think 3 cyl. kabota). It still does and I have not driven it since then which was 3 weeks ago. I limped it back home and drove my other truck to work. So after reading several possible things I checked all that I knew how to. The FICM is getting full voltage..a little over 48V, I pulled the EGR valve after much work and ended up breaking it as it was totally stuck in there..had to put a brand new one in. The new valve did absolutely nothing to fix it. Batteries are probably 2 years old, so I dont think that would do anything. The injectors are new. I returned the computer to stock..no difference. Just everything about it sounds funny. Starting it is hard all together now..almost like the starter is keeping it running sometimes until it will run on it own at super low RPM..like 250 rpm. Turbo sounds like it is spooling, but honestly the overall sound of the engine and the strange throttle response has me freaking puzzled to say the least.
The truck does not have EGR delete or anything, but I have never had issues with it. It is straight piped, turbo back. Running bully dog stuff on this truck for over 4 years. My other truck I use SCT stuff.
I need help here if anyone has some legit suggestions. I'm not a diesel mechanic, but a pretty mechanical guy and been driving powerstrokes since 1994. I'm just stumped.
The codes it kicked were the KAM one and then one that shows up if you unhook your batteries, cant remember the numbers. P1000 and P0603 maybe?

Fire away I would appreciate the help.

[Jrod78]

moving this thread as I see the 6.0L specific area now..sorry.
delete this one if you want.