Repetitive problems keeping same boost

[Justinf74]

I have problems keeping a steady boost pressure in my syclone, sometimes it will boost around 7 #'s and sometimes around 10 #'s, any ideas?

 

[GM TURBO]

Wastegate.

Wastegate adjustment.

Wastegate solenoid.

Clogged cat.

Knock. (You can move this to the top of the list)