What Tools Do You Need to Change Spark Plugs? [7 Great Options]

Have you ever wondered how the engine starts? Well, believe it or not, it is ignited by the tiniest bolt of lightning called spark plug.

The ignition for the combustion required to start your automobile is created by the spark of electricity that this plug generates over a short gap.

Spark plugs are low maintenance and do not require replacement often. However, most manufacturers suggest changing it every 30,000 miles to better fuel economy and reduce harmful emissions.

Newly changed spark plugs will also let you have an optimal combustion system and smoother starts. But, what tools do you need to change spark plugs?

What Tools Do You Need to Change Spark Plugs?

If you do it yourself, changing spark plugs takes around an hour (for a four-cylinder engine) and saves you at least a hundred dollars in labor.

Most of the time, it’s a straightforward job that will help you retain top performers and get the best gas economy possible.

1. Gap gauge

A gap gauge is an answer if you want to get the most out of your car. It improves the spark plug’s efficiency, guaranteeing that the spark plug ignites the air and fuel mixture required to power your car properly.

This tool also reduces the risk of burned electrodes, leading to spark plug failure.

If the spark plug isn’t suitable for your car, you may use the gap gauge to adjust it. And you’ll have the exact measurement recommended by the manufacturer.

2. Needle-nose pliers

Needle-nose pliers are useful in confined spaces. They’re great for cutting and bending small wires, gapping spark plugs, getting into hard-to-reach places, and tightening loose bolts.

If you use it for automotive work, you should opt for needle-nose pliers with long handles as they give a firmer grip and a longer reach.

Such attributes are perfect for helping you grip stuff in your car. The gripping strength of these needle-nose pliers is greater than that of the pliers with extra long jaws.

3. Spark Plug Swivel Socket With Extension

It might be challenging to remove an old plug at times. The good thing is that tools like the spark plug swivel socket can easily fit into small areas and lock in place. By using this, you can now easily replace your spark plug.

This spark plug swivel socket set can handle sensitive spark plug threads and is perfect for plugs with a rubber insert. If you have old spark plugs, the most suitable one you can get is the  5/8″ or 13/16″ socket wrench.

4. Handle Ratchet

If you value work efficiency, you must opt for a handle ratchet when tightening and loosening fasteners. You can use this tool with a smaller swinging motion, which is handy when there isn’t much space to move the handle.

Most of these handle ratchets feature a lock that prevents the socket from slipping off the fastener or sticking to it. Such details are important in making the work quicker.

You may also use this handle ratchet together with the swivel socket wrench to twist the spark plugs.

5. Spark Plug Boot Puller Pliers

In current COP systems, the ‘boot’ of the spark plug links the ignition coil to the spark plug. After a while, the boot may become stuck on the old plug.

Spark plug wires may also surround this boot, so you must be careful when handling it.

If there’s a faulty spark plug boot, the cylinder head and ignition coil might also be damaged. Using the long tip of the spark plug boot puller pliers, you can now gently extract the spark plug boot without damaging the spark plug wire.

6. Torque Wrench

If you have a new spark plug, you must maintain it properly to prevent engine damage and other issues. That is why you have to invest in a torque wrench.

When you overtighten the plugs with the spark plug wrench, it might cause the cylinder head to fail, whereas loose plugs will simply fall out after a few uses.

But with a torque wrench, you can adjust the tightness of the plugs in accordance with the manufacturer’s manual.

7. Wire Loom Spacers

Wire loom spacers allow you to neatly organize your wires and route them away from the harmful engine and exhaust heat.

They’re used in ignition systems that use a spark plug wire to transport the current to prevent electrical discharge to the ground and cross-firing.

Without wire loom spacers, a misfire may occur, affecting oil consumption, engine performance, and gas mileage.

Other Important Items

There are other items that can be helpful in spark plug replacement. They may not be necessary all the time, but they can certainly be of help:

1. Spark Plug Wires

When changing old, broken, or inefficient spark plugs, you can still reuse your current spark plug wires. After all, these are critical components.

Replacing your spark plug wires while installing new spark plugs is a good idea if you observe symptoms of wear and tear or other damage.

2. Anti-seize Lubricant

If you’re having trouble removing plugs, it’s likely because the previous installation didn’t use an anti-seize solution.

You can lessen the chance of spark plugs fusing to engine components by applying this product to them before the installation. When using an anti-seize solution, though, you’ll probably need to lessen the tension on each plug by up to 10%.

3. Distributor Cap

This section is only applicable to cars with distributors. Like the spark plugs and wires in your car, the distributor cap can also wear out over time.

So if you have this cap, you should examine it for any signs of damage after replacing the spark plugs and wires. If you notice any, replace the distributor cap immediately.

Frequently Asked Questions (FAQs):

How can I do a maintenance check on my car’s spark plugs?

Spark plugs are not troublesome as long as you change them according to your manufacturer’s recommendations.

However, you should still check them from time to time to know if they can still perform their job properly.

If you want to examine your spark plug, here’s how to do it:

With a Spark Plug Tester:

1. First, make sure to unplug the spark plug lead to the spark plug.
2. Next, attach your spark plug tester to the ignition wire and the other end to your spark plug.
3. Then turn the ignition on and start your engine.
4. Observe if your spark plug will glow. If not, this could mean a problem with your spark plug or your ignition system.

Without a Tester:

1. Remove the ignition wire.
2. Next, detach the spark plug from the engine using a spark plug wrench.
3. Then, connect the ignition wire again to your spark plug. Please make sure that their metallic parts touch each other.
4. Turn your engine on and look for the spark or glow.

What’s the price for spark plug replacement?

Depending on what spark plugs you need and the number of cylinders in your engine, a set of spark plugs can cost anywhere from $16 to $100.

When calculating the cost, you should remember that certain specialist engines have two spark plugs per cylinder.

If yours requires two spark plugs per cylinder, your expense will definitely be higher. And if you can’t change it on your own, the labor charge should cost around $40 to $150.

What is torque?

Torque is a measurement of the force which causes something to rotate around a point. It is calculated by multiplying force by length. In simple terms, torque is the amount of work an engine can exert. It’s also known as the pulling power.

In a real-life scenario, you can imagine it’ll be difficult to turn a bolt if you use a small wrench. On the flip side, it’s easier to turn it once you use a longer one.

It’s because if you put the same force to the wrench, then multiply it by their length, the longer one will obviously have the higher result.

What’s the difference between tensioning and torquing?

Torque is the measurement of the force needed to rotate something, such as the turning force required to spin a nut around a bolt’s threads.

On the other hand, the stretch or elongation of a bolt that generates the clamping force of a joint is known as tension.

Can I use a normal socket for spark plugs?

Yes, you can use a regular socket for spark plugs as long as you put grease inside the plug to pull it out. You may also use spark plug boots or a magnet as alternatives.

A standard deep well socket will work as well. Additionally, there is no rubber grommet inside a plug socket, so you must be careful not to harm the porcelain insulators.

What size socket is required for spark plugs?  

The 5/8″ spark plug socket is commonly used by mechanics. However, the size of your spark plug socket is totally dependent on your car.

You should also remember that the spark plug’s hex size is important. This hex size is the socket that’s necessary for installation.

A spark plug’s hex size refers to the diameter in the center of the plug that may be used to tighten or loosen it. 5/8″ and 13/16″ are the most common hex sizes. There are, however, spark plugs with hex sizes as tiny as 8mm on the market.

What torque is best for spark plugs?

Gasket spark plugs use a crushable gasket to produce a seal between the plug and the combustion chamber, hence the name.

On the other hand, tapered seat plugs use the outer shell of the spark plug to form a seal between the plug and the combustion chamber.

But if you were to choose between the two, go with the gasket spark plugs as it is recommended by manufacturers when an old plug is re-installed.

Can I still use a spark plug when I drop it?

A Ford service technician mentioned that you should never use a spark plug that has been dropped as a rule. If the gap is still within specification and the ceramic is not shattered, you might be able to use the plug.

However, you should take note that even minor damage to a spark plug might result in misfires.

You should also be careful in examining the damage because it might not be visible at first. And if this results in damage to your engine, you might spend a lot of money repairing it.

It’s also important to check whether the plugs have internal electrics. If you have no idea, try to search for the model on the Internet and watch Youtube videos.

Can I remove a spark plug without any tool?

You can’t remove a spark plug without a tool. Removing requires a spark plug wrench. The plug will blow off in use if it is loose enough to remove by hand.

Most of the time, spark plugs are located in deep areas so that they can only be reached with a wrench.

How do I know which spark plug size I need?  

You might get confused by the various types of spark plugs. But reviewing your owner’s handbook is the simplest way to figure out which one you need.

You should remember that the correct plugs for your car will be specified in the handbook.

Tools for Success

If you are knowledgeable about your car, replacing the faulty spark plugs is a chore that you can usually complete over the weekend.

However, you must first know what tools you need to change spark plugs. With the right information and a bit of planning, you can definitely succeed in replacing your spark plugs.