I have a 2006 F550. It has a factory boost gauge. Recently it has started intermittently having boost problems. Most of the time it is fine but at least a bunch of times a day, it will build ridiculous boost for no reason while im driving. I let off the throttle and it will back down to normal. Usually it will do this a couple times then it will go back to functioning normal. It is not the gauge... it is definitely spooling up more than it should be at times. Most of the time it is fine so I am not thinking it is a sticking vane problem as I have had that on other trucks and taken care of it. This is different because it is only intermittent and it goes away. I do not know much about the vgt solenoid as far as testing it or anything else.
Any ideas at all are helpful. I tried to list everything that could help.
I do have acces to a snap on scanner
it does have an egr delete with replacement up pipe