When Should You Replace Spark Plugs in a Car?
2 Answers
You should replace the spark plugs in your car if you experience any of the following conditions: difficulty starting the engine, reduced power, excessive exhaust emissions, or increased fuel consumption. 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 guidelines in your owner's manual. Here are some general standards for spark plug replacement: platinum spark plugs should be replaced at 40,000 kilometers, standard nickel alloy spark plugs at 20,000 kilometers, and iridium spark plugs between 60,000 to 80,000 kilometers. Steps for replacing spark plugs: Open the hood and remove the engine's plastic cover. Disconnect the high-tension wires, making sure to mark each cylinder's position to avoid confusion. Use a spark plug socket to remove each spark plug one by one. While removing them, check for any external debris like leaves or dust, and make sure to clean the area thoroughly. Insert the new spark plug into the spark plug hole, hand-tighten it a few turns, and then use the socket to tighten it properly. Reinstall the high-tension wires in the correct firing order, and then reattach the cover.
I've got experience with changing spark plugs. I've been driving that little car for three years, and smooth starts are the most important. Generally, manufacturers recommend changing them between 30,000 to 100,000 kilometers, depending on the material. Cheap copper plugs might need replacement at 30,000 to 40,000 kilometers, while expensive platinum or iridium ones can last over 70,000. Last time I delayed changing them, the car would shake a bit at startup, and fuel consumption shot up noticeably. After replacing them with new spark plugs, it improved right away. To save money, regular checks are key—like having the mechanic inspect the electrode gap during maintenance. Don’t wait until they’re completely worn out, or you might end up spending big on engine repairs. Also, different driving habits affect lifespan. For example, frequent short city trips wear spark plugs faster, requiring more frequent replacements. In short, follow the manual—don’t skimp and risk bigger problems.
