how to get base boost

[gmcturbo]

I'm trying to track down some boost loss. Do i just unplug the wastgate solenoid or do i run a vaccume hose from the wastgate actuator to the port on the turbo. i should get 8 psi right? My problem is i lose boost at about 7psi, it goes down to around 1 or 2 then comes back up on the highway around 35% throttle. datamaster shows no knock, constant tps %, and target psi is constant also when this happens. i have replaced the vaccume hoses on the turbo. truck is stock- i have a datamaster file if anyone wants to see.

thanks-
mike

 

[TYRODD]

unplug the harness from the solenoid, and say hello to better MPG (base boost)

 

[Divergent Lightning]

I had a problem with boost controll and it turned ou to be a bad solenoid. Being they are only $20 at the most, might want to try that out too.