I had the same problem with mine a couple years ago. The wire that runs from the spark knob to the burner had cracks in it. Make it dark, raise the stove top, turn the knob, and you see the spark from the crack in the wire to the bottom of the stove. Simple solution, tape up the crack in the wire. The insulation in the wire is very hard and brittle. After winter freezing, they can break. After all, it's just a plastic. You may have several places that are cracked. I simply taped the wire all the way and never had problems again. Like yours, it was only one burner. Nothing wrong with the burner, or the "sparker". Check this out before doing anything anything. Poking and prodding could cause more harm than good.