If you look at the rear of the engine, on the driver's side, you will see a rod running from under the heat shield to the wastegate actuator. From the actuator is a thin rubber hose which goes to the boost control solenoid.

Check to see that the hose is in good shape and well connected. Pressure in that hose opens the wastegate. A leak means the wastegate stays closed.

Check to see that the wiring and connector are intact and clean on the BCS.

With the engine cold, you can remove the turbo heat shield, and inspect the linkage, as well as check to see that the wastegate moves freely. You can disconnect the wastegate linkage from the actuator to feel the looseness of the wastegate, without having to remove the heat shield, if you so wish.

Good luck

Marty
'96 855T