Under What Circumstances Should Spark Plugs Be Replaced?

[StLuna]

Spark plugs should be replaced under the following circumstances: 1. Excessive electrode gap caused by spark plug erosion; 2. Abnormal carbon buildup and erosion in the car; 3. Quality issues with the spark plugs; 4. Signs of melted or rounded electrodes, erosion, scarring or cracks on the insulator, or carbon deposits. Symptoms of damaged spark plugs include: 1. Difficulty starting or unexplained stalling: Insufficient ignition energy fails to generate high voltage, preventing the ignition of the air-fuel mixture in the cylinder, making the car unable to start or causing sudden stalling even if it starts; 2. Reduced power and excessive exhaust emissions: This leads to incomplete combustion of the air-fuel mixture in the engine, resulting in insufficient power, black smoke from the exhaust pipe, and the emission of unburned harmful substances, causing the exhaust to exceed standards.