Will new spark plugs make a car run better?

Replacing spark plugs with new ones can indeed improve a car's operating condition, but the effect depends on the degree of wear of the original spark plugs. New spark plugs enhance combustion quality by optimizing ignition efficiency, which directly translates to more responsive power delivery, increased low-speed torque, and a reduction in fuel consumption by approximately 5% to 10%. For vehicles that have traveled over 30,000 kilometres, replacement typically results in noticeable improvements in cold start difficulties and idle vibration issues. This is because the new electrode gap can consistently generate a high-voltage spark exceeding 20,000 volts, ensuring complete combustion of the air-fuel mixture. Spark plugs made of different materials have distinct replacement intervals: copper-core plugs are recommended for replacement every 30,000 kilometres, single-platinum-core plugs every 60,000 kilometres, and double-iridium-core plugs can last up to 100,000 kilometres. However, turbocharged models require a 20% shorter replacement interval. Selecting NGK or Denso spark plugs that match the OEM heat range specifications, priced between 80 to 300 ringgit per set in the market, ensures optimal compatibility.