ICP high and Idle miss
I have 2004 6.0 with 120k. regular oil changes. Newer design with ICP on valve cover. I have had a rough idle issue for over a year that gets better and worse for no appearent reason. I thought it was a surging issue as i start to let of brake at a stop light i found that its definatley a miss not a surge. The only things I have found to be off are high ICP. I am pushing 4.5-4.8v icp at half throttle through WOT all the time measured by Edge guage and it is this way when in stock or stage 2 mode. checked for loose grounds, pulled IPR no damage or flakes, truck always starts and even when having bad miss at idle once you touch the accel pedal truck runs great and cant feel any misses at all while driving or towing. RPM guage at idle doesnt move at all when missing. Truck has never died or not started quick. Miss is getting worse but even the shop has no clue. FICM has constant 48.5 or 49v. FICM connectors found to have broke clips holding them in so I zipped the on but problem is the same. What would cause high ICP always. Could faulty IPR cause rough running. ICP looks good no oil in plug.
Im just looking for any ideas since the shop has none. Anyone have something like this happen. I dont think its stiction as it happens mainly when warm.