Regardless of the type of spark plug used by your car, chances are high that without proper engine maintenance, you could experience spark plug fouling. Fouled spark plugs cause misfires, rough idle, ...

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 ...

You can (and should) actually read your spark plugs for valuable "clues" about how your engine is operating. To read your spark plugs, follow these steps: 1. When you get the first spark plug out of ...