What are the symptoms of a faulty engine ignition coil?

1 Answers
CadenRose
07/28/25 6:04pm
Ignition coil failure manifests with the following symptoms: 1. Engine vibration: Once the ignition coil is damaged, the spark plug's inability to ignite the combustible air-fuel mixture can easily cause engine misfire, resulting in severe vibration. If multiple cylinders misfire 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 doesn't cause engine misfire, the weakened spark plug ignition capability will still affect the combustion of the air-fuel mixture, leading to adverse effects such as increased fuel consumption and reduced power. 3. Excessive carbon buildup: When the spark plug's ignition capability weakens, it also causes incomplete combustion of the air-fuel mixture. This incomplete combustion produces a carbonaceous deposit called carbon buildup, and the vehicle's exhaust may emit black smoke.
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