I had one with a similar problem u had, no codes, would happen VERY VERY VERY VERY Int. lose pedal and wouldnt do n e thing, glow plug light came on, for 2 sec then everything is ok. I drove that thing 30min then it acted up.
How i got it to happen in my stall was, get a prybar or brake depressor from the alignment machine, get the engine rpm's to about 1500-2000 rpm and just start shaking the harness. When i shaked around the bulk harness by the fuel filter the truck would go to a idle, my helper said the glow plug light went on, then would go back to the 1500-2000 rpm, till i wiggled the bulk part again.
Put a harness in it... buh bye...won a account /forums/images/%%GRAEMLIN_URL%%/rockon.gif