At work we have two of these truck.
Just got a call from the jobsite that one of them is doing an odd throttle/rpm surge.
it can be setting there idling, and all of a sudden 'takes off', then will act like normal.
No pattern, intermittant.
I know it uses a HPOP and no 'normal' IP, etc.
Since it has a turbo.. do these have a boost sensor and pedel sensor to figure fuel dump?
I'm heading out in a bit with a superchips code reader that is setup for 04 6.0PSD to see what I can find. Any tips or guesses will be appreciated.