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How often should you change spark plugs? These parts play a crucial role in the operation of a car’s combustion engine, influencing everything from acceleration to gas mileage. They need proper care if you want your vehicle’s engine to perform at its best.

Below, we’ll take a look at how often spark plugs need to be changed, and we’ll talk about what can happen if these parts aren’t replaced in a timely manner. We’ll also provide a step-by-step guide for changing your car’s spark plugs.

Timely Replacement Is Key

You can answer the question, “How often should you change spark plugs?” by taking a look at your car’s owner’s manual. The manual will list a recommended replacement interval. Usually, replacement is required every 30,000 miles.

If you don’t replace your car’s spark plugs in a timely way, you could be setting yourself up for engine problems such as misfiring, lack of proper acceleration and uneven idling. Failure to replace old spark plugs could also cause your car to consume excessive amounts of fuel.

How to Replace Your Car’s Spark Plugs

Replacing spark plugs will take roughly an hour if your vehicle has a four-cylinder engine. With a V6 or V8, it could take longer.

It’s a fairly straightforward task with four-cylinder engines, and if you have experience working under the hood, you should be able to handle the project yourself. However, the job gets more complicated with a V6 or V8. If your vehicle has one of these engines, you may want to turn the job over to a mechanic.

To handle this project, you’ll need:

  • Spark plug gauge

  • Goggles

  • Compressed air

  • Torque wrench

  • Swivel-head spark plug socket

  • Spark plug wire puller

  • Replacement spark plugs

  • Your car’s owner’s manual

Now that you have the tools you need, you’re ready to get started:

1. Clean the area around the spark plug using compressed air, making sure to wear goggles as eye protection. Removing dirt from this area will help prevent debris from entering the engine’s combustion chamber once the plug is unscrewed.

2. Remove the wire from the first spark plug, using a spark plug wire puller. Wait until each plug has been removed and replaced before moving on to the next wire. This will help make sure you attach the right wire to each plug.

3. Use a swivel-head spark plug socket to remove the spark plug. Turn the plug counter-clockwise to unscrew it.

4. In your car’s owner’s manual, locate the section that tells you how much of a gap there should be between each spark plug’s two electrodes.

5. Check the spark plug gap on the new plug before installation to make sure it aligns with the measurement given in the car’s owner’s manual. Utilize a spark plug gauge to measure the gap between the plug’s two electrodes.

6. If the gap needs to be adjusted, employ the spark plug gauge to handle the task. Use the gauge to bend the curved electrode until the correct gap is attained.

7. Install the new spark plug using a torque wrench. Be careful not to over-tighten it.

Regularly replacing your car’s spark plugs can help keep your vehicle’s engine in good health. This task is one you may be able to handle yourself.

Check out all the electrical & ignition system products available on NAPA Online or trust one of our 17,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on how often should you change spark plugs, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.

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