How many kilometers do spark plugs need to be replaced?
2 Answers
Spark plugs should be replaced after driving 40,000 to 60,000 kilometers under normal car maintenance conditions. However, this may vary depending on the brand and engine type. It is recommended to follow the user manual. You can refer to the following maintenance and replacement standards: platinum spark plugs should be replaced at 40,000 kilometers, ordinary nickel alloy spark plugs at 20,000 kilometers, and iridium spark plugs at 60,000 to 80,000 kilometers. Damaged spark plugs may exhibit the following symptoms: difficulty starting the engine, reduced power, excessive exhaust emissions, and increased fuel consumption. In such cases, the spark plugs should be replaced promptly. Steps for replacing spark plugs: Open the hood, lift the plastic cover of the engine, and remove the high-voltage distributor wires. Mark each cylinder's position to avoid confusion. Use a spark plug socket to remove the spark plugs one by one. While removing them, check for any external debris like leaves or dust and ensure they are thoroughly cleaned. 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 removed high-voltage distributor wires according to the firing order, and then secure the cover.
Old-school mechanics always emphasized regular spark plug checks. Different materials have vastly different lifespans—standard nickel alloys start degrading at 30,000 km, with electrode wear drastically reducing ignition efficiency. Mild symptoms include increased fuel consumption and sluggish acceleration, while severe cases lead to engine misfires and vibrations. Platinum plugs last at least 60,000 km, and iridium ones can endure up to 80,000 km. A friend of mine stubbornly waited until 100,000 km to replace his, only to find the ceramic insulator cracked upon removal, causing air leaks and severe combustion chamber carbon buildup. The safest approach is to check the electrode gap during routine maintenance—replace immediately if erosion exceeds 0.8 mm.
