Re: 99 4.2L v6 F 150 stumbles accelerating
Make sure the wires ends and the distributor cap (or whatever they plug into at the non plug end) are made of the same metel (eg copper and copper). If they are not (i.eg different coloured metals) the metal will tend to corrode rapidly causing the sort of problems you are having. Try claening these bits with spray contact claener lubricant and a stiff nylon brush and see what happens. If you can't get matching components use ignition lubricant on these parts.