I have an 04 f250 with 130k on it. The boost pressure will sometimes jump up 4-5 psi with steady throttle or even if the cruise is on. It started last fast then seemed to go away with the cold here in MN now that it is warm again it has started doing it again. The RPMs dont go up nor does my speed change. I had to change the FICM recently was hoping that would maybe solve this problem also unfortunately it didnt. I am running spartan diesels agg. street tune but it still does it if I put it back to stock.

 

How are you reading boost pressure? Have you cleaned the turbo and have you checked all your pipes and hoses for leaks?

 

This happened to me once. Had the dealer check mine out and it turned out to be the VGT Solenoid. Hope this helps.

 

I have an X monitor. I know its not just the gauge I can actually here the turbo wind up a bit when it does it. I have not cleaned the turbo but I did look for leaks and didnt find any.