Check, replace and maintain the spark plugs in your car or motorcycle with this easy guide.

Though small, spark plugs play an important role in getting your vehicle started and keeping it running—so when they’re past their prime, you’re going to want to replace them.

To test the operation of both the ignition coil and the spark plug, connect the tester between the spark plug boot and the spark plug. Then start the engine and watch the tester window.

You can use a multimeter to test the resistance to be sure. Q: How Can You Tell if a Spark Plug Is Firing? A: The grounding test is performed to determine if a plug is firing.

Car Care: Take cars that misfire to a repair shop, where their spark plugs and ignition boots should be checked.

A. No, the spark plug and ignition coil are two separate parts. The ignition coil feeds the spark plug high voltage. Q. Yeah, But How Much Does It Cost To Replace an Ignition Coil?

Keep your vehicle running in top shape by replacing the spark plug wires.