What are the symptoms of damaged car spark plugs?
2 Answers
Car spark plug damage symptoms include: 1. Difficulty starting; 2. Low power; 3. Excessive exhaust emissions; 4. Increased fuel consumption. The working principle of spark plugs is: The spark plug's ground electrode is connected to the metal shell, which is threaded into the engine block through the cylinder head. The electrode repeatedly generates electrical pulses, creating a high-voltage pulse that ionizes the air between the two electrodes, forming a spark and causing an explosion to ignite the air-fuel mixture in the cylinder, thereby starting the engine. Types of spark plugs include: 1. Standard spark plugs; 2. Projected insulator spark plugs; 3. Electrode-type spark plugs; 4. Seat-type spark plugs; 5. Pole-type spark plugs; 6. Surface-gap spark plugs.
When spark plugs go bad, the symptoms are quite noticeable. At idle, the engine shakes violently, and you can feel abnormal vibrations just by touching the steering wheel. Acceleration becomes sluggish—where the car used to leap forward with a light tap on the gas, now it crawls like an old man, and fuel consumption spikes. Last month, I spent hundreds more on gas during a long trip. Cold starts are difficult, with several instances where turning the key took multiple seconds before the engine fired up—utterly frustrating. The exhaust occasionally emits black smoke with a strange smell, almost like something’s burning. I recommend replacing spark plugs early; they should be checked every few tens of thousands of kilometers to avoid worsening carbon buildup and damaging other components, which could lead to costlier repairs later. Periodically pop the hood to inspect the spark plug electrodes—if they’re too dirty or worn, swap in new ones. Those handy with tools can DIY, but otherwise, a repair shop is the safer, hassle-free option.
