What is the difference in spark plug heat range?
2 Answers
The difference in spark plug heat range is as follows: 1 to 3 is low heat range, 4 to 6 is medium heat range, and 7 to 9 is high heat range. The higher the heat range, the faster the heat dissipation. Its functions are: 1. To introduce the high voltage electricity generated by the ignition coil into the engine cylinder; 2. To generate sparks between the spark plug electrode gap to ignite the air-fuel mixture, ensuring the engine operates normally. The method for removing a spark plug: 1. Clean the dust and impurities around the spark plug using compressed air or a soft tube to blow them away; 2. Ensure the engine is in a cold state before proceeding; 3. Immediately protect the spark plug installation port after removal to prevent any impurities or dust from entering the cylinder; 4. Be careful not to damage the insulating ceramic body when using a wrench; 5. When adjusting the spark plug gap, do not bend or strike the center electrode.
The difference in spark plug heat range mainly lies in the speed of heat dissipation. Through decades of driving older cars, I've found that the heat range directly affects engine temperature control. Spark plugs with a higher heat range dissipate heat more slowly, making them more suitable for low-speed city driving when the engine isn't running too hot. Those with a lower heat range dissipate heat faster, making them better suited for high-speed driving or aggressive performance. Getting it wrong can cause various issues. If the heat range is too low, the spark plug may accumulate carbon deposits leading to unstable idling. If it's too high, the engine may overheat and potentially get damaged – my car once developed increased noise because of this. I recommend checking your engine manual to select the matching heat range and having a mechanic test it during regular maintenance. Don't make random changes – safety comes first, and it can also save you fuel costs.
