plugs

Matt, I can't believe the porcelain has gone bad. It's an impervious ceramic. I would look for a foreign substance shorting out the external porcelain. Some cases of this happened years back by shysters selling cheap anti freeze which was nothing more than salt water and in a few days, particularlly under heavy humidity, the salt water seemed to seep through the cast iron engine and contaminated spark plugs, wires, distributor caps, rotors and coils and even after heavy steam cleaning some of the parts would have to be replaced. If the coil or distributor was involved there was no way you could start an engine so contaminated. Even a residue of unrinsed engine cleaning soaps could deliquesce (draw moisture) under high humidity conditions and form an electrical path to ground on the outer porcelain of the spark plugs. If not this, then some other similar condition must exist. The only other thing I can think of now is that glycol anti freeze leaked into a cylinder cavity. That would short out a plug.Go figure