How to Choose Spark Plugs?
2 Answers
When selecting spark plugs, it is essential to ensure that the dimensions of the old spark plugs match those of the new ones. The dimensions of the spark plugs are printed on the ceramic insulator of the skirt. Even if you can't understand them, just make sure the numbers and letters on the new and old spark plugs are identical. Steps to replace spark plugs: Open the hood, lift the plastic cover of the engine, and remove the high-voltage distributor wires. Mark each cylinder's position to avoid confusion. Use a spark plug socket to remove the spark plugs one by one. While removing them, check for any external debris like leaves or dust and ensure they are thoroughly cleaned. Place the new spark plugs into the spark plug holes, hand-tighten them a few turns, and then use the socket to tighten them further. Reinstall the removed high-voltage distributor wires in the firing order, secure the cover, and then start the engine to check if the spark plugs are functioning properly.
Choosing the right spark plug comes down to my years of driving experience. I've driven everything from old Santanas to modern cars, so picking the wrong spark plug is not an option. First, check your car's user manual to find the factory-recommended type and heat range. What's heat range? Simply put, it's how heat-resistant the spark plug is. If you often drive in mountainous areas or hot weather, a higher heat range is more suitable; for winter or flat regions, a lower heat range will do. You should also know a thing or two about materials: copper plugs are the cheapest but need frequent replacement, typically wearing out every 20,000–30,000 km; platinum and iridium plugs are more expensive but last 40,000–50,000 km, with stable ignition and better fuel efficiency. The size must be a perfect match—otherwise, it won’t fit or ignite properly. For brands, I recommend NGK or Denso—they're reliable and durable. One last tip: don’t cut corners when replacing spark plugs, as it affects ignition. If your car shakes or has trouble starting, check immediately—safety first.
