i have an 84 dodge w150 manual four wheel drive with a 318. so i have been workin on this rig for a few weeks now tryin to get it smoged and today i started it up and when the choke kicked off it died. it runs when you keep your foot on the gas but dies as soon as it hits the idle mark. i have changed the plugs wires cap roter rebuilt the carb all the vac lines are new and in order the timing is set where it should and i even put a new suel filter on it today and it didnt help. any suggestions to what it might be?