Originally Posted by
CMR
If you disconnect the actuator and move the wastegate arm on the turbo by hand can you hear the penny moving inside? You should hear it clink, if not the weld has gone.
As for your theory - you are thinking of it in reverse, the actuator has to be stiff to hold the penny closed to build boost, then it bleeds off pressure allowing the penny to open to maintain a steady pressure. If the penny is allowed to stay open then boost won't be built at all until high in the rev range.