How to Identify Spark Plug Materials?

[DelTaylor]

Spark plug materials can be identified by the central electrode core. A thicker core indicates a standard type, while a thinner white-colored core signifies platinum, and a thinner yellow-colored core indicates iridium. Platinum spark plugs should be replaced at 40,000 kilometers, standard nickel alloy spark plugs at 20,000 kilometers, and iridium spark plugs at 60,000 to 80,000 kilometers. Spark plugs are installed on the side or top of the engine. In earlier models, spark plugs were connected to the distributor via ignition cables, but over the past decade, most car engines have been updated to feature direct connections between ignition coils and spark plugs. Working principle of spark plugs: The ground electrode of a spark plug connects to the metal shell, which is threaded into the engine block via the cylinder head. The insulator primarily serves to isolate the metal shell from the central electrode. The terminal nut is the part of the spark plug that contacts the high-voltage coil. When current passes through the terminal nut and central electrode, it ionizes the medium between the central electrode and ground electrode to generate a spark, thereby igniting the air-fuel mixture in the cylinder.

[DelCole]

I usually enjoy tinkering with my car, and changing spark plugs is a routine task. The simplest way to check the material is to pull out the spark plug and directly observe the electrode part—copper electrodes have a yellowish-brown color, feel slightly heavier, and are prone to erosion with black spots; platinum ones are shiny, silvery-white, and more durable; iridium ones generally have a more premium shine. Don’t just rely on color—carefully look for the marking codes on the spark plug casing, such as the alphanumeric combinations from brands like Bosch or NGK. You can confirm the material type by checking the manual online. Remember, choosing the wrong material can cause engine shaking or higher fuel consumption, so match it to your car model. Wear gloves before working to avoid oil stains interfering with your observation.

[LeCarter]

In car enthusiast groups, I often share experiences. Identifying spark plug materials isn't difficult, just focus on a few key points. First, remove and inspect the electrode color and condition - copper spark plugs have yellowish center electrodes that wear easily, while platinum ones are shinier and more heat-resistant. Secondly, pay attention to the small markings on the spark plug tip - each brand has specific codes, like ACDelco's metal symbols, just take a photo with your phone to look them up. Material greatly affects performance - copper spark plugs have shorter lifespans and are suitable for regular cars, while platinum ones are better for long-distance driving. Don't change them based on gut feeling - using the wrong material can cause ignition issues and malfunctions. Safety first, don't skimp on this.

[AliviaFitz]

After driving for half a lifetime, I've learned to guess spark plug materials by their appearance. Copper spark plugs are affordable and practical, with electrodes that appear dark yellow and tend to accumulate carbon deposits after some use. Platinum ones are more expensive but shine brighter, stay cleaner, and withstand high temperatures better. Don't overcomplicate material identification—new spark plugs show clear color differences in their electrodes, while older ones reveal wear patterns. Those that wear out quickly are usually made of copper or ordinary steel. Using the wrong material leads to odd engine noises, sluggish acceleration, and higher fuel consumption. Sticking to the manufacturer's recommended type saves hassle when replacing them.