First thing that comes to mind when there's issues during the cold is something loosened up and it's creating a fault. It could very well be the gas cap itself which I've seen before. But also it could be something else to do with the evaporative emissions system where there's a leak on one of the hoses. That's located underneath on the passenger side. Check the rubber seal on the gas cap to see if there's any cracking. The gas cap itself has a built-in valve that could also be an issue. Other than swapping with an identical gas cap and testing, you may need to replace it and see if it goes away. If not, the evap system, the gas tank hoses are the next culprit.
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