How Often Should Spark Plugs Be Replaced in a Car?
2 Answers
Under normal maintenance conditions, car spark plugs should be replaced after driving 40,000 to 60,000 kilometers. However, this may vary depending on the brand and engine type, so it is recommended to follow the user manual. The following standards can be referenced for maintenance and replacement: 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. Steps for replacing spark plugs: Open the hood, lift the plastic cover of the engine, and remove the high-voltage wires. Mark the position of each cylinder to avoid confusion. Use a spark plug socket to remove the spark plugs one by one. While removing them, check for any external debris such as leaves or dust and ensure they are thoroughly cleaned. Place the new spark plugs into the spark plug holes, hand-tighten them a few turns, and then use the socket to tighten them further. Reinstall the removed high-voltage wires in the firing order and secure the cover.
I've worked in auto repair shops for many years and found that spark plug lifespan depends on the material. Nickel alloy ones typically need replacement every 20,000-30,000 km, platinum can last 50,000-60,000 km, while iridium is even more durable, reaching 80,000-90,000 km. Driving habits also matter significantly - frequent stop-and-go traffic accelerates spark plug wear. Once had a customer complaining about sudden fuel consumption increase, and upon inspection, it was indeed severe carbon buildup on the spark plugs. I recommend having technicians check electrode condition with a borescope during each maintenance. Replace immediately if the gap is too wide or the ceramic is cracked. Don't wait until experiencing cold start difficulties - by then it's already affecting engine performance.
