http://catalog.worldpac.com/mercedesshop/sophio/image.jsp?title=Spark%20Plug%20Connector&url=http%3A//img.eautopartscatalog.com/live/F101084561BER.JPG

This is the weak point on 104 Waste Spark ignitions.
Change them under each coil. [ 3 total]

Re-read post # 3.