[Laird Scooby]

What does the boost gauge do on deceleration? Also under normal acceleration, is it boosting to where it always did or higher, lower or what?

If you don't have a boost gauge, is the car feeling livelier, less lively or about the same?

In addition to Kays suggestion of the inlet manifold gasket, a known trouble spot, i'm wondering if there is a split hose on the wastegate, seized dump valve, split diaphragm in the actuator or similar.