Join Date: Sep 2005
Location: Damascus, Oregon
This might be unrelated, but, last winter I was in Edmonton, Alberta with my Freightliner. The alternator belt got so cold it started to slip on the alternator pulley. Don't know if it's a good idea for a car, but I got a big sheet of cardboard from the warehouse I was delivering to, and blocked all but a bit of the radiator. This kept the engine compartment warn enough that the problem was solved.
Made the heater work better to. That was -35, way colder than I care for, you don't even dare to shut a Diesel off in those conditions.
Also, it's possible that you had a little ice on the alternator brushes, and as soon as they warmed up, it worked fine.