Hi to all , I am new to this forum ,I fond this thread and I relait to the same problem , I have a 86 190D whit a 5 speed transmission so far I deed :
-Replaced Injection pump whit a rebuild unit.
-Replace injectors
-Replace chain tensioner
-Replace clutch / pressure bearing / pressure plate / shaft bearing
-Replace flex joint rear and front
-Replace center shaft bearing
-New shacks / new tires
-New motor mounts
-I remove the harmonic balancer from the shaft It was in pretty bad shape.
All the above done and I have the same problem.
I don't have a damper on the throttle linkage , I don't even have a mount for it .
tinker_er you have found the problem ?
I suspect the timing device but again just under 50% , this jerkin drives me crazzy .