Will the engine malfunction light come on if there is a problem with the spark plug?
3 Answers
If there is a problem with the spark plug, the engine malfunction light will come on. Criteria for judging spark plug damage: Damaged spark plugs may exhibit the following symptoms: difficulty starting, reduced power, excessive exhaust emissions, and increased fuel consumption. Components of a spark plug: A spark plug mainly consists of a terminal nut, insulator, terminal stud, center electrode, side electrode, and shell. Spark plug replacement interval: Under normal maintenance conditions, 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 used as a reference for maintenance 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.
A faulty spark plug can very likely trigger the engine malfunction indicator light, as spark plugs are responsible for igniting the fuel. Once ignition becomes unstable, the engine will experience misfires. Modern vehicle engine control units continuously monitor sensors—for instance, when misfire counts in a cylinder exceed the threshold, the malfunction light is immediately activated as a warning. I've seen many cases where aging or carbon-fouled spark plugs cause the light to stay on persistently. However, this doesn't always happen immediately—occasional minor issues may trigger the light briefly before it turns off. If the light stays on, it indicates the ECU has detected a serious problem. Promptly scan for trouble codes to prevent more severe engine or catalytic converter damage. Regularly inspecting spark plug condition during maintenance can significantly reduce this risk.
When there's an issue with the spark plugs, the engine malfunction indicator light usually comes on. From my years of driving experience, this is quite common. Once the vehicle starts, if the spark plugs fail to ignite multiple times, the computer system immediately detects it, such as reading misfire trouble codes, and the light will either flash or stay on steadily. Once, my old car had worn-out spark plugs, causing the engine to shake and sputter, and the light came on too. After replacing them with new ones, the light went off. This reminds us to pay attention to routine maintenance, checking the spark plugs every 20,000 to 30,000 kilometers and cleaning carbon deposits in time. Ignoring the light not only reduces power but may also lead to other component issues, like a significant increase in fuel consumption. In short, don't delay when this happens—find a reliable mechanic to check it out.
