Spark plugs that haven't been changed for a long time can become one with the cylinder head. Fortunately, it's possible to repair damaged threads instead of scrapping the head. (Photograph by Chris ...

How often you replace spark plugs depends on the type of plugs you have. You may have 30,000-mile plugs, or if the plugs have platinum tips, they may be good for up to 100,000 miles, although some ...

The space, or gap, between the center and side electrodes needs to be an exact distance across; otherwise, your plugs don't fire efficiently. Adjusting the distance between the two electrodesis called ...

Spark plugs sit at the center of every gasoline engine’s heartbeat, turning fuel and air into the controlled explosions that move your car. When they work properly, you feel smooth power, quick starts ...

For the average stocker in good running condition, spark plug selection is a cinchchoose whatever brands on sale, look up the plug part number in the catalog, and go down the road. At the opposite ...

For hot rodders, spark plugs are often nothing more than inspection tools that reveal whether an engine is running too rich, too lean, or just right. Street guys look for a nice tannish-brown tint on ...

For the average stocker in good running condition, spark plug selection is a cinchchoose whatever brands on sale, look up the plug part number in the catalog, and go down the road. At the opposite ...