Random Rail pressure issues

Truck is a 2004 305/555 nv5600. I have removed all after market programming, alone with the rail pressure gauge trying to eliminate the problem. The truck had been fine it sat for 4 weeks while i was out of town and now this issue has popped up. When cold the truck starts fine and runs normal. It seems like heat causes it to flair up, because i haven't seen any issues on a cold engine. Anyway It will be crusing down the road and all the sudden cough and rail pressure goes to 1,100 psi and it knocks a little bit and white smoke pours out of the exhaust. ( enough to clear the interstate) I usually bump it to neutral and let off the throttle (which isn't doing anything anyway) It will eventually catch itself and then spike rail pressure to 24-25,000 then come back down. Sometimes it will keep doing, others you can go a mile or 2. At an idle i can make it happen by burping the throttle, so its not load dependent. Sometimes its bad enough it will hardly idle or die, other times its idling with a slight miss and there is a white haze out of the exhaust, other times it is unnoticeable and seems normal, these times it will shut off and start without hesitation. The weirdest thing is it will return to normal out of nowhere without any signs. It will randomly pop a cam sensor code, i'm not sure if its it or not. I scoped the cam and crank sensor with a scanner and they were dead on with rpms and never skipped a beat, rail pressure on the scanner was the same as my gauge, and i could never find anything electrical after logging for 45 min. I have changed the fca to no avail. I've owned tons of these trucks and never have seen this. I'm going to double check the crosstubes and lines, what about injectors? could a sticking pintle do this, or a bad cp3? Or should I do the cam sensor? Ive searched and read about the wires chaffing at the a/c compressor, and about the fca plug, but wouldn't that show up in the electrical system while i was logging the sensors? Thanks in advance