How to Replace Spark Plugs?

[BradyLee]

Spark plugs need to be replaced under the following conditions: the car exhibits symptoms such as difficulty starting, low power, excessive exhaust emissions, and increased fuel consumption; the spark plugs are severely damaged, with signs like blistering, black streaks, cracking, or electrode melting at the top. Methods to determine if a spark plug is damaged: Remove the spark plug and observe its appearance color to assess its condition. A normal spark plug has an insulator skirt and electrodes that appear gray-white, gray-yellow, or light brown. A properly functioning spark plug has a reddish-brown insulator skirt, an electrode gap between 0.8-0.9mm, and no signs of electrode burn. If the spark plug is covered in oil or deposits but is not damaged, it can continue to be used after cleaning off the oil and deposits. If the spark plug is severely damaged, with signs like blistering, black streaks, cracking, or electrode melting at the top, the cause of the damage should be identified. After troubleshooting, replace the spark plug with a new one. Additionally, if the spark plug appears black as if smoked, it indicates that the wrong heat range was selected or the mixture is too rich, with oil seeping up.