CN ran into problem recently with it's ET44AC's where the engine air intakes are equipped with a temperature sensor. Seems they're set to shut the unit down if the intake air is below -35deg C... and with some nighttime temps around -50deg C across the prairie and northern Ontario, they began to drop like flies. From what I was told they were ordered to keep south until modified to allow lower temps. Of course, this is a major issue because they need all their DP equipped units in the coldest regions in order to provide air in the middle and/or tail end of those 10-12,000' trains, lol.
I'm not sure if anyone here is aware of what's happened to CN out west, but it's analogous to UP's post SP takeover meltdown. Short on power to begin with, straining under the weight of record tonnage, too few men, and then hit with extremely cold weather... total mess. Have a friend that sat in a siding so long that he ordered pizza and had it delivered to the headend! Same guy spend an entire shift pumping air in his consist and had to be relieved without ever leaving the terminal. A friend riding VIA #1 out of Toronto, who is still not in Vancouver btw, the train being 37hrs late, faced the prospect across three prairie subdivisions of having to meet 48 westbounds on a 90% single track RR.
Anyways, there's a reason why the 90 former Oakway SD60's CN acquired have kept or had their winterization hatches reinstalled.
