What are the symptoms of faulty car spark plugs?

[VanJeremiah]

The symptoms of faulty car spark plugs include: 1. Electrodes becoming rounded and insulators developing scars; 2. Causing the engine to produce excessive carbon deposits; 3. Electrodes melting and insulators turning white; 4. Difficulty in starting the car; 5. Black smoke from the exhaust pipe; 6. Rough idling; 7. Excessive exhaust emissions; 8. Insufficient power. Car spark plugs are categorized into: 1. Standard spark plugs: The insulator skirt slightly recedes into the shell end face, with the side electrode outside the shell end face; 2. Insulator-protruding spark plugs: The insulator skirt is longer, protruding beyond the shell end face; 3. Fine-electrode spark plugs: The electrodes are thin, characterized by strong sparks and better ignition capability.