first replace your fuel filter theres one under the hood and there might be one on the passenger side frame rail then if that doesent work you could replace your spark plug wires it could also be a problem with your coil, ignitor
also pull the float bowl cover from your carb and check to make shure there arnt any deprease inside it i had a very and i mean very small chunk of gasket in mine that every now and then would get sucked up and cover the opening of one of the jets and would cause a similar problem to what your expeariancing
good luck