Must Spark Plugs Be Replaced If They Leak Electricity?
3 Answers
Spark plug breakdown, major head leakage, spark plug air leakage, and spark plug oil leakage are common phenomena when replacing spark plugs. If a spark plug is damaged by electrical leakage, both the spark plug and the ignition coil's ignition wire need to be replaced. The spark plug is a crucial component of a gasoline engine's ignition system. It introduces high-voltage electricity into the combustion chamber, causing it to jump across the electrode gap to create a spark, thereby igniting the combustible air-fuel mixture in the cylinder. Spark plugs are installed on the side or top of the engine. Early spark plugs were connected to the distributor via cylinder wires, but over the past decade, most car engines have been modified to connect the ignition coil directly to the spark plug. Steps for replacing spark plugs: Open the engine hood, lift the engine's plastic cover, 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 external debris like leaves or dust and ensure everything is cleaned thoroughly. Place the new spark plug into the spark plug hole, hand-tighten it a few turns, and then use the socket to tighten it further. Reinstall the high-voltage distributor wires according to the firing order, and secure the cover.
I remember that time when I was driving my old Santana to the countryside, and halfway through, the car started jerking and almost stalled. After towing it to the repair shop, it turned out to be a faulty spark plug causing the issue. The mechanic explained that the spark plug was leaking electricity, mainly because the insulating ceramic was cracked or the electrode gap was too wide, which over time would lead to misfiring. At the time, I thought I could just make do with it, but within a few days, the engine started shaking even worse, and fuel consumption skyrocketed. The mechanic warned me that if I didn’t replace it soon, the leaking spark plug could even damage the ignition coil, making repairs much more expensive. So, my takeaway is clear: don’t hesitate—replace a leaking spark plug immediately, as it affects both driving safety and engine longevity. Now, I make it a habit to check them regularly and usually replace them with a good set every 50,000 kilometers—it’s both hassle-free and cost-effective. Opting for iridium spark plugs makes them more durable, lasting an extra 20,000 to 30,000 kilometers, and can even give a slight boost in performance.
I've helped repair spark plug leakage several times. The most common causes are aging ceramic insulators or oil buildup, which cause the spark to misfire. During inspection, you can remove them to check for electrode erosion or cracks, and use a multimeter to test resistance—replace immediately if abnormal. If there's leakage, temporarily spraying with cleaner can help for a while, but cracked ceramics can't be repaired. Continuing to use them will only lead to unstable engine ignition, starting difficulties, or even distributor damage. Personally, I think spark plugs aren't expensive—a set for regular cars costs just 100-200 RMB. Replacing them is much more cost-effective than risky repairs. For routine use, stick to scheduled maintenance; spark plugs should be checked every 50,000-60,000 km—don't wait for issues to arise. In short, leakage means the part has failed, and not replacing it could trigger a chain reaction affecting overall vehicle performance.
