isx 15 boost problems

[JED]

looking for some help i have an isx 15 we deleted roughly 7 years ago. No issues, the customer brought it in thinking he had a turbo issue the problem is the boost surg's up and down, can feel it in the truck. other issue is it will build 20 psi boost by just reving it up in the shop. Could this be the ecm reset ive heard about in the past? Turbo swipe is fine, actuator passes calibration. Back pressure tube is clear, blew out intake pressure sensor.. No active codes to go by, no turbo related inactive codes either. Any help is apreciated