SYMPTOMS OF A BAD IGNITION COIL
purpose
The purpose of the ignition coil is to convert 12 volts from the battery up to 40,000 volts. This voltage goes into the spark plug to produce a spark. Then, the spark ignites with air and fuel to start combustion.
location
The location of the ignition coil depends on the engine and the type of ignition system in your car. In this article, we’ll be talking about the coil-on-plug ignition system. In this system, each spark plug has its own ignition coil. Spark plugs can be on top of the engine, divided between the left/right side, or divided between the front/back side of the engine.
Ignition coils typically last around 100,000 miles. If your car is around that range, it’s worth considering looking into ignition coils in your vehicle.
symptoms
engine light
The first symptom of a bad ignition coil is having an engine light on. Here are some codes that can pop up:
P0300 - P0312 (misfire)
In some cars, these codes can also show up:
P0350 - P0362 (ignition coil fault)
Ensure you can access your car's diagnostic codes by acquiring an OBD2 scanner here.
Rough idle
The second symptom of a faulty ignition coil is a rough idle. The ignition coil is responsible to send voltage through the spark plug for it to spark, so if it fails there won’t be a spark, leaving your car with a misfire. For example, if your vehicle has a four-cylinder engine and one cylinder has a misfire, your engine will become less efficient by a quarter, which explains the rough idle.
loss of power
The third symptom you might be experiencing is a loss of power. Due to misfires occurring in the engine, your car won’t be able to accelerate as fast.
smell of gas
The fourth symptom of a bad ignition coil is the smell of gas. If the ignition coil is slowly wearing out, it won’t send the full amount of volts needed for the spark plug to produce a great spark. This leaves the cylinder with unburnt fuel and air to travel out of the exhaust, resulting in the smell of gas.
Make sure there’s no corrosion on the ignition coil connectors as this could also cause the ignition coil to not work properly.
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