How to Identify Spark Plug Materials?

[OTravis]

The material of a spark plug can be determined by the central core of the electrode. If it is thick, it is a standard type; if it is thin and white in color, it is platinum; if it is thin and yellow in color, it is iridium. Related Information: 1. Introduction: The spark plug is one of the critical components in a car's ignition system. It introduces high-voltage current into the cylinder to generate an electric spark, thereby igniting the air-fuel mixture inside the cylinder. Factors affecting the performance of a spark plug include the gap between the electrodes, which should neither be too large nor too small. 2. Gap: If the gap between the spark plug electrodes is too small, the resulting spark will be weak, leading to carbon buildup and subsequent electrical leakage. If the gap is too large, the required voltage to bridge the gap will be higher, making the engine harder to start, especially at high speeds, potentially causing a "misfire." The main components of a car spark plug include: the insulator, shell, side electrode, center electrode, terminal nut, and terminal stud.

[StEverett]

To determine the material of a spark plug, the simplest method is to remove it and examine the small tip of the center electrode: copper ones usually appear dull and prone to black carbon deposits, nickel alloy ones are slightly brighter but oxidize quickly, platinum ones are grayish-white and more durable, while iridium ones are shiny and have the longest lifespan. When I repair cars, I usually check the markings on the spark plugs—for example, a 'P' might indicate platinum, and an 'I' could mean iridium. Recognizing these letters makes the job much easier. If the engine shakes or starts slowly, it's often due to worn or deformed electrodes on poor-quality spark plugs. Upgrading to a higher-quality material can improve combustion efficiency and save fuel. Copper plugs are cheap but need replacement every 10,000 to 20,000 kilometers, whereas platinum and iridium plugs, though more expensive, can last up to 100,000 kilometers. Learning this knowledge is quite practical for DIY car maintenance.

[JonathanLee]

Spark plug materials are super interesting! The thin part of the center electrode is the key: copper is the most common but turns yellow and gets dirty easily, while high-performance iridium shines like a gem and ignites super fast. When inspecting, look at the text markings on the spark plug—most brands engrave material codes like C for copper, N for nickel, P for platinum. After driving many cars, I found that better materials not only make the engine run smoother but also reduce carbon buildup. With poor materials, the electrodes dull and acceleration feels sluggish. If the electrodes turn dark brown when cleaned, it's time for a replacement. Upgrading to a better material spark plug boosts horsepower and saves money—DIY is really not hard to try.

[Gideon]

Identifying spark plug materials is quite simple: remove the spark plug and observe the shape and color of the center electrode. Copper electrodes are thick, prone to blackening, and accumulate more carbon deposits, while platinum ones are slender, grayish, and accumulate less carbon. The markings often include letters indicating the material—checking the vehicle manual alongside ensures greater accuracy. From my driving experience, different materials affect replacement frequency—copper ones need frequent changes for convenience, while premium materials offer a more cost-effective, one-time solution. If the engine idles unevenly, take out the spark plug for a look; poor-quality materials lead to faster carbon buildup and increased fuel consumption. During maintenance, remember to match the material to your car's performance—don’t overlook this small detail to save on major repair costs.