Ok so he quick... Purchased the truck three weeks ago, 2001 Chevy Duramax LS, Crew cab long bed 228k miles new cp3 pump, head gaskets, and injectors and injector lines. Paid 6k with check engine light and a P0463 (fuel sending unit?), and a P0380 (glow plugs or relay?). He purchased an '04 with a manual trans. Drove it through its paces for a week or so, did my best not to be rough on the old girl (that many miles makes me nervous) got my Edge Evolution CTS, mainly for the monitoring and the ability to get slightly better fuel econ and towing my travel trailer, not for all out drags. Plug it in and it says the truck isnt stock programming, reset to stock. I did, then the next day I get p0463, p0380, and a p0700... Weird, lame, oh crap moment. Reset codes. Does it again a couple drives later, always shifts good never any issue. Initiate trans relearn, shifts crazy hard, as in you can hear tire chirp on down shift, all settles out after a coulle short trips. Reset codes the p0380 comes on, the others dont for a day, i keep checking every 5 minutes of driving and as soon as the p0463 comes on so does the p0700 code same time odd, same general area). I go to the dealer pull the following codes and then reset them we double checked the letters and numbers:

P0380 (glow issue)
P0463 (sending unit)
P0700 (tcm light)
P1860
P0C09
B088B


They dont, know what they mean, and suggest google search. Turns up nothing new, hitch up trailer and drive north up and down good sized hills load up trailer and head home, trans temp never rises above 181*, ect 201* shifts great. Come home and have the dealer re-scan codes:

C010C ?
C086B ?
C20D1 ?
C2B10 ?
P0380 (Glow issue)
P0463 (Sending unit)
P0700 (tcm light)
P096C ?
P0C09 (drive motor "b" phase U-V-W circuit low
P1041 (only found SAAB specific code)
P1860 (TCC PWM cause open/short?)
P2208 (Nox sensor heater sense circuit (dealer) according to almighty google air flow restriction between filter and maf?

I have since replaced the glow plugs, some were very old and a few new ones, I like all new. Was going to replaced the relay, but I am getting 12v at the first glow plug on driverside, and by the time it reaches the front its about 10v the wire goes over to passenger side has good continuity, And will not illuminate the 12v test light on passenger bank, but the glow plugs get a jumpy 40ish volts? wtf???? So i second guess my meter, replace batteries, test the truck battery reads solid 12.4 volts, test continuity negative to head (good) neg to frame (good) neg to block (good). So I am not sure what to check now or where to go. I have a local trans guy that will check it out tomorrow, but anything I can do tonight to try and relieve some outgoing cash would be great!!!!!

 

For anyone who finds this in the future, I had the internal wiring harness on the trans mission replaced and the fuel sending unit, all codes are now gone except for my p0380 glow plugs, which I need to address too. Its been close to a month now with no code issues.