What are the symptoms of a faulty ignition coil?

[LeSophia]

When the ignition coil fails, the following symptoms may occur: 1. Engine vibration: Once the ignition coil is damaged, as the spark plug fails to ignite the combustible gas mixture, it can easily cause engine misfire, resulting in severe vibration. If there are too many misfiring cylinders or two adjacent working cylinders misfire simultaneously, the engine may fail to start normally. 2. Increased fuel consumption and reduced power: Even if the ignition coil damage does not cause engine misfire, the weakening of the spark plug's ignition capability will still affect the combustion of the engine's combustible gas mixture, leading to adverse effects such as increased fuel consumption and reduced power. 3. Excessive carbon deposits: When the spark plug's ignition capability weakens, it can also cause incomplete combustion of the combustible gas mixture. The incompletely burned gas mixture produces a substance called carbon deposits, and the vehicle's exhaust may emit black smoke.