Cold weather related?

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-10.html#post1985158

The problem could be dirty motor oil. If you don't change the oil at the intervals recommended, small bits of carbon can begin forming in the oil due to even the smallest amounts of blow-by. Those bits of carbon can then get pumped to the injectors by the high pressure oil pump to actuate them, and the carbon can clog up the screens in the injectors. On top of changing the oil regularly, I personally would also recommend using Z-Max, or an equivalent product like Slick-50, as long as it's rated for diesels. It helps to break down existing carbon in your engine, and also helps keep any new carbon deposits from forming so it stays suspended in the oil, and goes away when you change the oil.