Lack of power above and beyond the typical lackluster performance.
Be sure and check the pressurized hoses to and from the turbo to intercooler and inlet manifold.
Have fixed one that had a hose split underneath that wasn't in view, but was leaking most all the boost out the underneath side of the hose.
Uncle "Richard" Douglas has a Land Rover with big wheels that never gets stuck... until he breaks something so it won't go. Uncle Douglas always breaks something. - Anna Crowther at the Conclave 2012 (AKA Carburetor Neck)