[Aiden]

You'd need a mityvac to test the actuator and it should start to open at 7psi iirc

 

[Aiden]

As you've been pulling on pipes etc and it's got worse since, I'd check all the vac lines to everything else are still good, if you already haven't done so.

Also get the turbo actuator tested, especially if it's the original. If it's busted then that will usually only show 1/4 boost on the guage, mine did and I too switched the boost solenoid twice before testing the actuator which was shot so I switched it for the turbosmart iwg75.