Should the Leiling spark plugs be replaced at 100,000 kilometers?
2 Answers
Leiling spark plugs should be replaced every 40,000 kilometers. Methods to determine if spark plugs are damaged: Remove the spark plugs and observe them. The condition of the spark plugs can be judged based on their appearance and color. Normal spark plugs have a skirt and electrodes that appear gray-white, gray-yellow, or light brown. A properly functioning spark plug has a skirt that is reddish-brown, with an electrode gap between 0.8-0.9mm, and no signs of electrode burning. If the spark plugs are covered with oil or deposits but are not damaged, they can continue to be used after cleaning off the oil and deposits. If the spark plugs are severely damaged, with signs such as blistering at the top, black streaks, cracks, or melted electrodes, the cause of the damage should be identified. After troubleshooting, replace the spark plugs with new ones. Additionally, if the spark plugs appear black as if smoked, it indicates that the wrong type of spark plug (too cold or too hot) was selected, the fuel mixture is too rich, or there is oil leakage.
My Corolla and Levin are sibling models, and my 100,000 km driving experience tells you: the original spark plugs really need to be replaced. Although the manual states a replacement interval of 100,000 km, after reaching this mileage, you can clearly feel the car occasionally shaking a couple of times when starting at low speeds, and the fuel consumption is about one liter more than when it was new. The electrode gap of the old spark plugs removed had long exceeded the standard value, and the carbon deposits in the combustion chamber had thickened. If you persist further, the ignition coils might also develop problems, leading to even higher repair costs later. Now, replacing them with iridium spark plugs only costs a few hundred yuan, which is much more cost-effective than a major overhaul. My advice is not to delay.
