What would cause the back three wires to arc like that. the wires are autolite and look fairly new. not real sure when wires were replaced.
I am going to assume that you are talking about plug wires, with the high energy coils of today if there is any flaw in the wires it will burn through in a short period of time. I would recommend getting a good set of plug wires like Belden or Accel and don't forget to apply a little dilelectric grease on the boots to ease with replacement of the plugs later on, but use sparingly.
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