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How-to » Engine » Fuel & Ignition » How to Replace Spark Plugs
 Note: This is a general guide for all vehicles.

How to Replace Spark Plugs

  • Spark Plug
  • Spark Plug Boot Removal Tool
  • Spark Plug Gapper
Safety Tip:
Always wear safety glasses when working on your vehicle. Wear other personal protective equipment (PPE) when necessary, for example latex gloves or closed toe shoes.

Park your vehicle on a level surface and allow the engine to cool down. Open the hood and locate the spark plug wires. Before working under the hood, make sure the hood struts are strong enough to support the weight. If the struts are weak, use a prop to keep the hood from falling.
Remove the spark plug wire boot from the spark plug terminal. Grip the boot with a plug wire removal tool to prevent the plug wire and boot from pulling apart.
Remove the spark plug from the cylinder head using a spark plug socket, extension, and ratchet. Inspect the condition of the spark plug. A normal burning plug will have slight electrode wear and a brown to grayish-tan color.
Check the gap on the new spark plug. If necessary, adjust the spark plug gap to the specification located in the vehicle owner's manual or on the hood decal.
Install the new spark plug by hand. If the threaded hole is hard to access, attach a 1/4 inch rubber hose to the end of the spark plug. Once the plug is threaded in, pull off the hose.
Torque the spark plug to the manufacturer's specifications and install the spark plug wire. Repeat the above procedure for the rest of the spark plugs. Replacing the spark plugs one at a time will prevent mixing up the wires.
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