Whether high-priced spark plugs are worth buying depends on the vehicle's engine type and actual usage needs; it is not absolutely true that the more expensive, the better. For naturally aspirated engine family cars, the original factory-specified nickel alloy or platinum spark plugs (approximately RM30-RM120 per piece) can fully meet the usage requirements for 30,000-60,000 kilometres. Blindly upgrading to iridium models (approximately RM100-RM300 per piece) results in almost no perceptible difference in power and fuel consumption, and may even cause ignition abnormalities due to mismatched heat values. The lifespan of spark plugs is strongly related to the usage scenario; for vehicles that frequently drive short distances, even if high-priced spark plugs are used, their actual lifespan may only be 70% of the nominal value. It is best to choose 4S stores or authorised repair shops for standardized operation with torque wrenches to avoid ceramic body cracking or cylinder damage caused by improper installation. Overall, when purchasing, one should base the decision on the recommended model in the maintenance manual and calculate the long-term cost in combination with the annual driving mileage. For example, for a turbocharged car that travels 20,000 kilometres annually, choosing an RM800 iridium set (replaced every 80,000 kilometres) is more economical than an RM300 platinum set (replaced every 40,000 kilometres).
