How to Replace Spark Plugs

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The spark plugs are what give spark to your engine. In order for your car’s engine to operate properly, it needs the proper amount of air, the proper amount of fuel, and the proper amount of spark to ignite them, which creates the combustion process that allows your engine to operate powerfully. If you have improper mixture, the car will run roughly. The average life of spark plugs vary from 30,000 miles to 60,000 miles. Keeping the spark plugs for 100,000 miles could very much hurt your engine, which would require an engine rebuilt to fix. As the spark plugs get older, they start giving duller sparks, which takes away from the performance of the engine. Having dull spark plugs can also affect the fuel consumption of your vehicle. Overtime, one or more of your spark plugs could get completely burnt, this can cause your engine to run roughly or not even start at times. It’s important to replace the spark plugs every 30,000 miles; however, if you’ve just purchased the car or if you haven’t been keeping track of your maintenance, there is a way to check the condition of your spark plugs. You just need a deep spark plug socket to remove the spark plugs, and then you can check their tips. A healthy spark plug shouldn’t have a black, burnt tip. If your spark plugs have burnt tips, then it’s time to replace them. Spark plugs should always be replaced as a set and not individually. If you purchase cheaper-end spark plugs, you will need to gap them. In which case you have to research the proper gapping for your specific vehicle, and make sure the tip’s gap is at such. However, most modern spark plugs now don’t require gapping. You just need to know the proper torque for your vehicle. The average torque for 14mm thread plugs is seven to 15 lb. ft. The average torque for 18mm thread spark plugs is 15 to 20 lb. ft. So if you can’t find the proper torque for your specific vehicle, this is a good average torque for you. The process of replacing the spark plugs is very similar for most vehicles. If your car is equipped with a V8 engine, you will have eight spark plugs to replace, if it is equipped with a V6 engine, you will have six spark plugs, and if it’s a 4 cylinder, buy four spark plugs for it. Read on to learn how to replace your spark plugs and give your car some life.

Tools Required:

Deep socket (5/8 or 13/16)
Wrench with extension
Torque wrench
Anti-seize gel
Spark plugs

There is a spark plug on top of each engine cylinder in all cars. Each spark plug has a wire connected on top of it. If your car is equipped with an engine cover, remove it. Most engine covers are snapped in place by a series of clips, so you can just pull it up. However, if you see a bolt or a screw, remove it first to free the engine cover.
Follow the spark plug wires to find the spark plugs.
If you have a newer vehicle, your spark plugs could be located under the ignition coils, which is the same place, but this time you have to remove the ignition coil by removing its bolt (sometimes they don’t even have a bolt, you can just pull it straight up), then pull the whole boot straight up. The spark plug will be sitting inside the hole.

If your spark plugs have the wires on top of them, gently pull the wire off of them. You can jiggle them left and right as you’re pulling them up to remove them.
Use your spark plug socket to remove the spark plugs. Simply turn the spark plug counter-clockwise to remove it.
If your spark plugs are under the ignition coils, remove the electrical connection connected to the coil by sliding the red tab back, and then remove the coil by removing the bolt holding it in place, and then pull it straight up. Now you can insert your deep socket with the extension inside the hole and turn the spark plug counter-clockwise to remove it.

Before installing the spark plugs, rub some anti-seize on their threads. This will prevent them from getting stuck in there, which can give you major issues later on.
Install the spark plugs in place, turn them clockwise to tighten, and torque them to the proper torque of your specific vehicle, or follow the average torque in the introduction above.
Install the wires on top of the spark plugs and make sure they are snug in place.
If your plugs were under the coils, then install the boot in place, tighten the one or two bolts holding it in place, and then connect the electrical connection to it.