Merlinmagic07

okay this is the second time this has done this since i have had it. its been cold here past few weeks(ohio) and i useually keep the engine block heater on to keep it warm. well the 2 times i havent its haveing a REALLY hard time starting like i tryed for 2 hours and FINALLY got it running fine. the other day it just wont start it like turns over fine and it will fire and then it will die and it wont start i have killed my batt trying to and after a bit of trying for a while it will finally staret i have to give it gas and it will idle the exaust smells like gas a bit and then its fine no whining from the fuel pump and i had the pressusre checked and its fine. well it hasnt done it for a week and i JUSt got done wgetting it running again and i have NO idea whats going on. it has a 5.2l in it. but now today i mean when i got it started it idles fine it revs fine it drove around the neighbor hood fine and when i turned it off and tried again it wants to die but it doesnt. could it be like a auto choke or something. PLEASE HELP