How many kilometers does a car need to drive before replacing spark plugs?

[FelicityLynn]

Spark plugs generally need to be replaced after driving around 30,000 kilometers. The replacement interval varies depending on the material of the spark plugs: yttrium spark plugs should be replaced every 30,000 kilometers, platinum spark plugs every 50,000 kilometers, platinum spark plugs every 80,000 kilometers, and platinum-iridium alloy spark plugs every 100,000 kilometers. Methods to check if the spark plugs are in good condition: 1. Healthy spark plug electrodes should be pale yellow; black electrodes indicate an incorrect air-fuel mixture ratio. 2. If they appear oily, it suggests a misaligned spark plug gap or excessive fuel supply, or a short or open circuit in the high-voltage wire. 3. If the deposits are black, it indicates carbon buildup on the spark plugs and bypassing.