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Hey guys, I've been fighting a heavy bucking and surging issue for some time now. My truck is essentially undriveable, and Id appreciate any insight on where to go from here. Symptoms: Ranging from light to heavy throttle input as long as the engine is under some load, it will develop a violent surge at about 35mph plus. It surges and bucks very badly and on my test drives within a couple miles of my house, its all I can do to nurse it home. It sounds like the footage youve seen of a WWII fighter getting shot down, when it starts to sputter before it catches fire. It idles just fine, and once I get it down to about 20mph it starts to behave again. It seems to worsen when the truck is warmer and the weather is colder. There are no error codes present. I believed I had fixed the issue previously, because the #2 injector line was not sealing correctly and air was getting into the line. I discovered a marred crossover tube which was replaced and now all the the lines are bone dry. I had one successful test drive about a week ago, where I went about 5 miles without issue. If I recall, it wasnt super cold that night (40's or thereabouts) Recent repairs and relevant performance modifications: Industrial injection Silver 62 turbo and II 120hp injectors Quadzilla Adrenaline Iquad running the stock V2 tune (I have a clue that the timing here could be low for the injectors, its about 13 at idle, and I have not been able to keep my eye on the phone while driving to see what it is at when it starts to miss) Newish ECM from auto computer specialists New VP from DAP All upgraded Battery cables and WT ground mod done Alternator testing at .03VAC Timbo APPS New Cummins MAP and Cam position sensors recently as preventative maintenence Fuel pressure rock solid (perhaps even a bit high) at 22psi with the fleece dual intank system and fresh fuel filter Fresh fuel All ECM VP grounds etc are new and clean I have checked and rechecked power and grounds to the vp and ecm many times. Id greatly appreciate any ideas on what to test next. I miss driving my truck!