I have a 06 3500 48re 4x4, mods are cai,5” exhaust and edge juice w/attitude.

When warm (whether the edge is connected or not) it has a lope to it, can’t hear it in the motor only the exhaust, if you rev the engine in neutral it hangs and slowly steps back to idle, and at 38-42% load (according to the cts2) the truck surges.

Rail pressure has a 200-300psi fluctuation at idle. And there is about a 15-20rpm fluctuation with the lope at idle.

Something is telling me injectors but I want some other opinions.

Thanks for any and all help.