Like title says, that's my problem. Quite a bit of cranking then finally starts with white smoke. Idles for about 5 minutes then rpm's dwindle to a sputter then it stalls if I don't hit the pedal. If stalls, then hard start again. Fuel system I'm thinking. Air leak maybe? but no visible leaks when off. Been burning some clean kero with additive lately with diesel mixed in here & there. Fuel filter only has about 1K miles on it but it's been on the truck for almost 2 years. As you can see I haven't driven truck that much in last 2 years. 215K on odometer. Replaced fuel lines some time ago with all marine hose, supply & return. Fuel module in tank was replaced as well. Fuel heater is long ago gone too. Any ideas on what might be giving me my problem? Thanks for any input my friends... ... .