What Are the Common Faults of Spark Plugs?
3 Answers
Common faults of spark plugs include: 1. Spark plug leakage; 2. Black deposits on the electrode; 3. Fracture at the top of the insulator; 4. Oil accumulation on the spark plug; 5. Spark plug erosion; 6. Excessive spark plug gap. The function of automotive spark plugs is to discharge the high-voltage pulse electricity delivered by the high-voltage wire, breaking down the air between the two electrodes to generate an electric spark, thereby igniting the mixed gas in the cylinder. Types of spark plug products: 1. Standard spark plugs: The insulator skirt is slightly recessed 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 outside the shell end face.
Last time my car had issues, there were multiple spark plug failures. The most common problem was carbon buildup, with the ignition end covered in black soot, preventing the spark from jumping and causing slow engine starts and shaking. Next was incorrect electrode gap - too wide or too narrow both weakened the spark, making the car jerk while driving. Electrode wear is another chronic issue - prolonged use causes erosion and deformation, reducing ignition efficiency and skyrocketing fuel consumption. There's also oil contamination when leaks dirty the spark plugs in the combustion chamber, preventing ignition. More severe cases involve cracked spark plug bodies from overheating or impact. These faults often cause engine misfires, poor acceleration, and even damage engine components. I routinely inspect them every 20,000 km or as manual suggests - checking gaps, cleaning or replacing dirty ones promptly for worry-free and safe driving.
Common spark plug issues at work are quite numerous. For example, carbon buildup, especially with frequent short trips where soot easily accumulates, leading to poor ignition and engine sputtering. Abnormal gaps are also common; improper maintenance can cause the gap to widen or narrow, resulting in weak sparks and vehicle jerking. Electrode wear is an aging problem; after a few years, the center electrode becomes rounded, performance declines, and fuel consumption increases. Oil contamination is another headache, where leaking valve seals dirty the spark plugs, leaving them black and unable to ignite; in severe cases, cracked spark plugs causing air leaks are even worse. These issues can make the car run rough, lack acceleration, and affect driving. During regular maintenance, always check the electrode color and gap—prevention is key, don’t wait for a breakdown to fix it. I always remind my car enthusiast group about this small but important detail.
