What Are the Signs of a Failing Ignition Coil?

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The signs of a failing ignition coil include backfiring, starting issues, lowering gas efficiency, engine misfiring, vehicle stalling and worn out spark plugs. The most common symptom of a faulty ignition coil is when the car runs for a while and the engine dies abruptly. This happens when the ignition coil or module becomes too hot.

The ignition coil is responsible for taking power from the battery and relaying the power to the spark plugs. This ignites the fuel and makes a car run. The severity of the symptoms of a failing ignition coil varies depending on which ignition coil is failing.

A bad ignition coil sometimes causes a vehicle to not start at all. Additionally, an automobile runs poorly and stops erratically during the drive. The vehicle also backfires when the exhaust system emits unused fuel. The way to detect this is when the exhaust emits a black smoke and smells of gasoline.

Oftentimes, problems with starting a vehicle occur due to ignition coil failures that cause the spark plugs to receive inadequate amounts of charge. It is best to run a car for 30 minutes and rap the module with a screwdriver head. The ignition coil is most likely faulty if the car engine dies.

Moreover, when a vehicle achieves fewer miles for each gallon of fuel, there is a possibility of ignition coil failure. This happens because the car uses more fuel to compensate for the insufficient power transfer.