Problem solved ...
Received the overload relay last Friday (Feb. 23) from FastLane and replaced it. Car ran fine during a short test drive. Reset the check engine light (unplug #31 fuse for 10 seconds). Drove the car on Saturday and Sunday for about 100 miles in total. The car runs fine and the check engine light never comes up again. Thanks.
BTW, my cruise control didn't work during the period when I had the cold start problem. It works fine now with the new overload relay installed. Apparently they are related.
Harry (94 C280)