Well, after two weeks at the shop, the car is back. After we pulled the first set of codes, we started seeing many problems in the engine compartment. There were missing disconnected vacuum lines, no hookup to the EGR system, bare wires in the starter harness, etc. There were many more things to be upgraded that aren't worth mentioning.
We did an oil-filter change and were shocked to see the most crudded up, collapsed oil filter the mechanic had ever seen. While this poor car had been serviced by Mercedes for the first 120K, it was ignored the next 50K.
It has been started 10-15 times since our upgrading and the strange initial starting problem has not returned.
We added Auto-RX to the oil and will start the cleanup since the sludge buildup was ghastly. The car runs like a dream, passed CA smog with flying colors and will now get the loving care a CE deserves.
My wife and I are taking a picnic lunch and a bottle of wine and are driving to Borrego Springs today to see the desert wildflowers..... in our new (to us) CE.
Thank you Arthur and the others who made suggestions originally.
Anziani