The rate at which a spark plug wears out will vary depending on the make and model of the vehicle, the type of engine, driving conditions, and spark plug type. Engines with copper spark plugs ...
That's the standard repair service on the recent Ford V8s that blow out spark plugs. <BR><BR><BR><BR>Ok, I kid, I kid. It's only standard when the shop can't sublet the head out to a machine shop.