Well, we pulled the alternator and took it to an electrical shop. They found that there was some solder on the "ground" side of the voltage regulator and some possible arcing. Ah Ha, I thought. This is it! Replaced the regulator, hooked up my VOM and drove the car. Voltage stayed at about 13.8 VDC. The car ran perfectly for 3 days and on the 4th, the strange problem returned. (loss of power after a block on a cold engine, no ASR light, cured by restarting the car, never to happen again during the rest of the day.)

In reading the posts on faulty OVP relays, it doesn't seem to correspond to those problems but I will have to try another relay to see if this is the culprit.
Anziani

'93 300CE 172K
'95 E420 117K