How To Gap Iridium Spark Plugs – Become A Mechanic Yourself!

Little do you know, aside from other vehicle familiar concerns, how to gap iridium spark plugs is one of those you should no way fail to bear in mind.

“Doesn’t it seem like a bit too tricky to get the hang of?” Many might think so, as it sounds like a specialized spectrum. Worry no more with our in-depth guide to walk you through every minor detail!

What Is A Spark Plug?

A spark plug, so-called a sparking plug, is an internal combustion engine component that has two electrodes isolated by an air gap.

Through the small spark generated between these two electrodes from the high-pressure ignition system, the spark plug ignites the air-fuel mixture as fuel is atomized and air reaches the engine’s cylinders.

To do so, the electrodes and the insulator between them must be capable of tolerating high temperatures.

Yet, the insulator also has the quality of handling electric stress up to thousands of volts well.

The gap of a spark plug’s mission in this operation is to maintain the length that benefits the spark energy. 

Meanwhile, the insulator’s shape leaves a certain impact on the conducting temperature.

If it is too cold, there’s a possibility the operation will result in carburization and gap shorting; if it is overheated, then an initial phenomenon is more likely to occur.

We can encounter a spark plug in several distinctive materials, with Nickel, Copper, Iridium, and Platinum being the most prevalent.

Many producers also utilize a little piece of ceramic as an insulator on this engine part.

Regardless of types, this part is vital in any automobile, as a faulty spark plug can lead to severe problems like thumping noise when driving.

Spark plug replacement work

What Are NGK Iridium Spark Plugs?

Thanks to its advanced technology, NGK Iridium spark plugs are among the best-performing types of spark plugs globally. 

Speaking of features, these components function as a thermo-edge design for the central electrode and employ highly valuable Iridium metal at the tip of the center electrode, which has a diameter of 0.6mm.

Unlike any ordinary spark plugs, its exquisite Iridium patterns allow you to run your vehicles at the smoothest and longest operation through miles. There is a chance you can get the most straightforward starting and greater combustion. 

Even better, exceptional acceleration over expanded mileage and lower electrode wear rate is no longer far-reaching in such a case.

What about the benefit of the special thermo edge design for center electrodes? If excellent antifouling conductivity is what you are looking for, then we would say seeking no further than NGK Iridium spark plugs!

Old spark plug car

Do You Need To Gap Iridium Spark Plugs?

Is it necessary to gap NGK Iridium spark plugs? The answer is a big old yes!

The better spacing the spark plugs are, the more optimization your engine can perform at. That is why it matters that much for you to get the knack of the NGK spark plug gap size chart and follow it thoroughly.

One way or another, you can view it as a consequential chain of action. 

Here comes the details: This characteristic has an impact on the engine’s fuel and air combustion.

And that, in turn, will have an impact on the car’s performance. The gap thus needs to be wider for more sparks to form, leading to an increase in the engine’s efficiency.

This broadening may be in effect in some instances, such as with customized engines. When gapping spark plugs, you must pay close attention to adjustments and measurements.

Otherwise, you risk yourself making unrepairable mistakes.

Importance Of The Spark Plug Gap 

As we’ve mentioned above, the spark plug gap plays a vastly vital role in running your car’s movement perfectly.

That said, there is not much choice for you to choose from. You must ensure the plugs have an appropriate gap, or your engine performance is on the decline.

This clearance in the midst of the side and center electrodes is in demand of being positioned right so that arcing at the proper voltage ignites the fuel and provides the combustion that runs the engine.

NGK Iridium spark plugs

How To Gap NGK Laser Iridium Spark Plugs

Step 1:

The first step on how to gap Iridium spark plugs is to find a feeler gauge or a gap gauge.

Step 2:

Remove the spark plug and clean it. This step will not matter much in how to properly gap iridium spark plugs if yours is brand new.

Yet, in case you’re testing a spark plug that is already in the car for an extended time, the contact points may get dusty and need purification.

Take note for your daily reminder: Don’t ever tidy a spark plug with abrasive materials!

Step 3:

The next step is to measure the existing gap in the spark plug. To determine the exact number, you need to run your feeler gauge or gap gauge through the electrodes. 

Once you have a measurement, record it and compare it to the recommended setting listed in the manual to see if it’s the right direction to go or not.

Step 4:

It’s now time to make whatever needed adjustments.

To Increase The Gap Size

Bend the ground strap up to the required height with a spark plug gapping tool or needle-nose pliers.

Beware to never allow the gapping tool or pliers to contact with porcelain or the Iridium center electrode. 

To Decrease The Gap Size

Follow the same procedure as before. Nevertheless, instead of bending the ground strap up, bend it down to the appropriate height.

Note: 

  • Remember to be extremely cautious when making any modification. Saying so, you should in no way bend the electrode more than a few thousandths of an inch. Though the engine part is tough, it’s not built to withstand a lot of tension.
  • Besides, avoid hitting the central electrode. If the center electrode gets damaged by excessive prying or the bottom electrode might have accidentally snapped off, it may then be time for you to get the new one.

Call to mind that when it comes to prying precious platinum core electrodes or metal iridium, they may be highly sensitive.

That’s why it’s critical to utilize the right spark plug gapping tool for doing the task.

Step 5:

Using a calibrated gapping tool to re-check the gap. Repeat the procedure of adjusting the tool until it fits snugly between the electrodes.

Also, don’t ever conduct the testing process with a round gapping tool. Otherwise, a permanently damaged spark plug is on the way.

How To Check Gap Laser Iridium Spark Plugs

How to check NGK spark plug iridium gap may not be as daunting as you might think once you know the ultimate simple way to get it done right. 

Step 1: Get The Equipment

All you have to do is merely pick up a fitting measurement on your feeler gauge or gas gauge. 

Step 2: Measuring

In the case you can no way locate the correct tool within the gap, it is in the circumstance of widening.

What if the tool doesn’t even touch the electrodes while being through the gap? Then, it must be too large and demand a narrowing.

Another situation is that the tool and the gap fit perfectly together. Then, congratulations for no more adjustments needed!

In most circumstances, gapping your Iridium Power plugs is not at all essential. The ultra-efficient firing power architecture will adjust itself for slight deviations in the factory set gap, even if they are little.

If you opt to re-gap your Iridium spark plug, do so with caution since incorrect gaping can harm or even destroy the porcelain center or Iridium center electrode.

Old spark plugs

Consequences Of Improper Spark Plug Gap

What happens if you don’t gap your Iridium spark plugin the way it should be? The consequences may then strike terror in your mind.

In that case, engine issues are inevitable. There is a high likelihood your vehicles will suffer the symptoms as follows, including misfires, increased plug wear, spark plug fouling, loss of power, or even poor gas mileage.

That way, neither too small nor too wide a gap benefits your motor running. If the gap is so tiny, it can give rise to the weakness of a spark.

Due to this, it’s impossible for the combustion process to finish successfully. 

What about too broad? Then, it might cause the spark plug to not ignite properly, resulting in misfires at uplifted speeds.

Torque Recommendation

Plug SizeIridium heads
N.mlb-ft
10mm flat seat10 to 157 to 11
12mm flat seat15 to 2511 to 18
14mm flat seat35 to 4026 to 30
14mm taper seat9 to 207 to 15
18mm flat seat43 to 5232 to 38
18mm taper seat20 to 2715 to 20

(1 N.m = 0.1020 kgf.m)

In case you’ve been tracking down for some useful suggestions, then you’ve landed in the right place! 

The figure above shows the recommended torque to install the spark plug accordingly. 

However, please note that you should apply these installation torque values in the table to fresh spark plugs with no previous threads lubrication only.

Otherwise, you should lower the numbers by about one-third to prevent unnecessary overtightening.

In A Nutshell

That’s how you grasp how to gap iridium spark plugs. No longer troublesome, these little tricky details are for you to idealize your automobile conquest!

Hopefully, our article can be of great use to you. Let’s roll up your sleeves and do your DIY project. See you then!

Leave a Comment