What Causes Carbon Buildup on Spark Plugs?

[SanMelanie]

Spark plug carbon buildup can be caused by an excessively large engine ignition advance angle or improper spark plug selection. After cleaning, new spark plugs should be replaced. Steps for replacing spark plugs: Open the hood, lift the plastic engine cover, remove the high-voltage distributor wires, and mark each cylinder's position to avoid confusion. Use a spark plug socket to remove the spark plugs one by one. During removal, check for external debris such as leaves or dust and ensure thorough cleaning. Place the new spark plug into the spark plug hole, hand-tighten it a few turns, and then use the socket to tighten it further. Reinstall the high-voltage distributor wires in the firing order, then secure the cover. Spark plug replacement intervals: Under normal maintenance conditions, spark plugs should be replaced every 40,000 to 60,000 kilometers. However, this may vary depending on the brand and engine type, so it's recommended to follow the owner's manual. The following standards can be used as a reference for maintenance and replacement: 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.