This the vehicle is rarely used but was always reliable until now, I use it as a work truck, plowing and hauling a trailer. The truck sat for 5 months. I started it 3 or 4 time during that time. Now winter is here I start it put the plow on and wait for the storm. In the middle of the storm I go out start it and plow one strip and the truck stalls unable to restart. When I try to restart I notice check trans light flashing. I add transmission fluid that was low. Few hours later try to start again and it starts sputtering like maybe bad gas is working thru. It finally starts and seems running fine again. I continue plowing several hours and locations miles apart with no problems no check trans light flashing. 2 days later new snow storm, go out start it no problem get 1 mile away and truck stalls. Me and a friend jump start for and hour or more started once but soon as i put it in gear it stalled. If I hold the gas pedal to the floor while turning it over it will sputter a few times then die. My initial thought were bad gas since the vehicle had been sitting for over 5 months with that gas in it. I tried dry gas, water remover ect. No luck. I have the truck towed home and I pull the gas line after the filter and gas is pumping strong thru there. While I have the line open I decide to drain all the old gas and put in fresh gas. When I turn the engine over it will not start at all but if i hold the gas pedal to the floor while turning it over it will sputter a few times then die right out. A few days later. I turn the key and it starts up. Runs beautiful again! New snow storm comes I start it up get half way thru plowing and it dies again same symptoms. Any ideas what could be the problem? It seems it's not a fuel problem. I should add when I was thinking fuel problem I removed the air intake hose and sprayed starting fluid into the intake and it did nothing.