Originally Posted by Mxfrank

That actually depends on which year and model we're talking about. For example, the 124 2.5's have vacuum operated waste gates, while the very same engine in an earlier 201 would have a pressure actuator. You can tell by where the actuator hose connects...if it connects to the turbo involute, it's a pressure actuator. If it connects to a vacuum switchover valve, it's vacuum operated. I wonder if a punctured wastegate diaphagm could cause this problem.