Low boost problems

[f100cleveland]

My truck has had the turbo cleaned, the egr cleaned, the pcm reflashed but the boost problems are still there. In stock mode I run 27-28 but if I put on any tune from my sct flash my boost goes down to 22-23 lbs. I get a blast of smoke at launch on the performance setting then just a hint of smoke after that. It seems to go good but why the lower boost? I reformated the tuner to the latest updates too. Is the turbo electronic activation system working right? Is it low fuel pressure? It was in the shop last week for a no start after it had been warmed up and driven a while. They drove it for a couple of days and it didn't do it for them and it didn't throw any codes. I wish it would just die then they could find out whats wrong. Any ideas on whats my problem??

 

[BamaSixGun]

The VGT solenoid might be worn out. How many miles on this turbo? Is it the original?

 

[f100cleveland]

26500 miles. Had boost issues fron day one.

 

[BamaSixGun]

Are all the sensors involved in good shape?

 

[f100cleveland]

Are all the sensors involved in good shape?

The dealer has had the truck 3 times for things related to boost issues and have had it on their scanner every time. They have taken it on 15-20 miles drives with the scanner hooked up takeing real time readings. Every thing checks out ok.