Can't say for sure, put you may have a couple issues. The cold temperature bucking, surging, stall could be the Mass Air Flow sensor. I had a similar problem with my daughter's 95 Contour Duratec V6. Only happened below freezing. After a few futile actions by the dealer, and no definitive code, they called over a young technician who went thru extensive Ford training courses. He drove it, it did it, and he was confident that the filament in the MAF was not properly sensing the change in the air mass due to cold air. Good news, was that it only took 15 minutes to change out, but the item was a bit expensive (and only available thru Ford).
It fixed my problem permanently.
(By the way, oxygen sensors are common failures on these engines at 55-60K, CEL will light) Good luck.
Al
