could be numerous reasons your pump could be bad your injectors could be clogged and so forth just take it to a mechanic sometime and tell them the issues and go from there
Have you checked your timing, checked your spark plugs each one make sure they all fire, slow fuel-- fuel filter clogged. big engines are usually hard to start when really cold!
prob thick oil starter not 100% weak battery plus batterys lose power as it gets colder If your going to take it to a mechanic, why even post here. Fuel pressure could be leaking off from the check valve in the fuel pump. What happens if you prime it?