08 6.4 loosing boost, boost gauge fluctuates alot...NEED HELP!!!

[Pipeliner_798]

I have a 08 f350 6.4 powerstroke with the SCT extreme livewire tuner, runnin the pre-loaded tunes, 5" strait piped exhaust turbo back, delete pipe has the sensors in place, put the egr delete plates without coolant flow on it yesterday, and a S&B intake...truck has 110k miles on it bought it brand new so I know what kinda miles are on it, flashed it an did dpf/cat delete at around 40k miles gave me some trouble starting at 50k miles thn eased off but just recently started again but worse, taking off sometimes it has no power then the boost kicks in after about 15 seconds @ 2k rpms, driving down the road feels like boost just shuts off completely then when I mash the gas peddle it revs up to 2200 rpms an kicks back on an sometimes drops back out within 30 seconds, boost gauge fluctuates alot, also checked dtc an only throws code u2023, anybody know what the problem might be?