Hey GD, i have not had any issues with cold weather (down to -25F). I did a post a while ago about what I learned about cold weather and diesel. In short; should be a non-issue with todays glo plugs and formulated fuels.
I am thinking you might have a problem with moisture (humidity)?
Any trouble codes?
Wish I could offer more....
*Life is Good-Camping all around the Continent*
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