Iridium spark plugs offer several advantages over conventional spark plugs:
1. Durability
Iridium is a very hard metal, which makes the electrode of the spark plug highly resistant to wear and corrosion. This results in a longer lifespan compared to traditional spark plugs.
2. Improved Ignition
Iridium plugs have a smaller and more efficient electrode design, leading to a stronger and more consistent spark. This improves ignition and combustion efficiency, which can contribute to better fuel economy and engine performance.
3. High Melting Point
Iridium has a significantly higher melting point than other metals used in spark plugs. This allows the electrode to remain stable at high temperatures, making iridium plugs suitable for high-performance and turbocharged engines.
4. Reduced Voltage Requirement
The smaller center electrode requires less voltage to generate a spark. This can lead to reduced stress on the ignition system and longer life for other components.
5. Precise Ignition
The fine tip of the iridium electrode produces a concentrated spark, ensuring more precise ignition of the air-fuel mixture. This can lead to smoother engine operation and reduced emissions.
6. Cold Start Performance
Iridium plugs can provide better performance during cold starts due to their efficient spark generation, helping the engine start more reliably in challenging conditions.
7. Compatibility
Iridium plugs are often designed to be direct replacements for conventional plugs, making them easy to install without the need for modifications.
8. Extended Maintenance Intervals
Due to their durability, iridium plugs often have longer replacement intervals compared to traditional plugs, reducing maintenance frequency.
9. Emission Reduction
The improved combustion efficiency offered by iridium plugs can lead to reduced emissions of harmful pollutants.
10. Consistent Performance
Iridium plugs maintain their performance over time, providing a more stable and reliable spark throughout their lifespan.
How to Change Spark Plugs
Locate the spark plugs - The spark plugs are threaded into the cylinder head and sit underneath the coil pack or plug wire boot. If you are having a difficult time locating the plugs, a repair manual for your vehicle is helpful.
Remove the coil packs or plug wires - First, put on the necessary safety equipment. This includes safety glasses. Gloves are optional, but highly recommended. To remove the plug wire, grip the boot and pull up while moving it side to side. If you aren’t careful when doing this the spark plug wire can tear out of the boot. This job can be made easier with the use of a dedicated spark plug wire removal tool.
Note: If your vehicle has spark plug wires, it’s a good idea to remove each wire and corresponding spark plug one at a time. This is so you don’t forget the order or routing of the plug wires. Alternatively, you can mark each wire with the cylinder number before removal. The bottom line is, engines having a firing order and the plug wires must be re-installed exactly how they were.
Remove coil packs - If your vehicle has individual coil packs the job is much easier. To remove the coil packs, start by removing the hold down bolt. This is a small bolt, usually with a 8mm or 10mm head. Once the bolt is moved, pull the coil pack straight up and out of the valve cover.
Remove the spark plugs - This step is where the magic happens. Wait until the engine is cool to the touch before doing this. Attach your spark plug socket to the end of your extension and ratchet. Once the engine is cool, insert the socket into the spark plug hole until you feel it grip the top of the plug. You should be able to push the rubber portion of the plug socket firmly over the plug.
Turn ratchet - Next, slowly turn the ratchet counter clockwise to loosen and remove the plug. As was stated above, it’s a good idea to replace the plugs one cylinder at a time so the firing order doesn’t get mixed up.
Old spark plugs next to new
Inspect the old plugs - Take a look at the old plugs before you toss them out. Plugs can reveal a great deal of information about the health of the engine. Normal deposits will be light brown or tan in color. If the plugs are physically damaged, black, wet or white suspect an engine problem.
Get the correct replacement plugs - Getting the correct plugs is as easy as going to coils-autoparts and specifying the year, make, model and engine of your vehicle. It’s crucial that you buy the right type of spark plugs, and that you buy quality replacement spark plugs for longevity. Of course, it’s a good idea to compare the old plugs to the new ones before installation.
Comparison of two different spark plug gaps
Gap the spark plugs(if necessary) - Start by inserting the spark plug gap gauge in the gap between the electrodes. Consult the repair information for your vehicle to determine the specified gap (the parts store will also be able to provide you with this information). If the gap is greater than specified, make it smaller by gently tapping the plug on a wooden surface with the gauge in between the plug gap until the desired measure is set.
Tip: Most modern vehicles use plugs that come pre-gapped to fit the particular engine application.
Install the new spark plugs - Place the plug into the end of your spark plug socket. Insert the socket and extension into the hole and gently thread the plug into the hold (turn it clockwise). Keep turning it until you feel the plug bottom out.
Note: Never over-tighten the plugs as cylinder head damage can result. If you are uncertain as to how tight the plugs should be, torque them to specification using a torque wrench. These specs can be found in the vehicle repair guide.
Re-install the coil packs or plug wires - To re-install the plug wires, simply place the boot over the tip or the plug and push down. You will know the boot is secure when you hear it click into place. If your vehicle has coil packs, just drop the coil pack into the cylinder. It does not need to click into place. Then, install the hold down bolt and tighten it down.
Spark Plugs FAQs
What are the different types of spark plugs?
There are five types of spark plugs: copper, platinum, iridium, ruthenium and silver.
How often should spark plugs be replaced?
Every car has a different standard for when its spark plugs need to be replaced. Typically, spark plugs should be replaced every 18,000 – 100,000 miles. Consult your car’s owner’s manual to see the recommended time frame to replace them.
What are the signs of a bad spark plug?
Signs of a bad spark plug or spark plugs needing to be replaced include:
- Check engine light is on
- Misfiring engine
- Issues with accelerating
- An abnormally loud engine
