1 Spark plugs with light tan or gray color deposits usually indicate a sound engine and ignition system. Plugs within this color range can have normal electrode wear of about. 005-to. 008-inch, which ...

Today, spark plugs are pretty easy to forget. In new Corvettes, theyseem to last forever. That wasn't the case years ago and, frankly, sparkplugs are often critical when it comes to performance and ...