Understanding (And Actually Addressing) Your Check Engine Light

Your car’s check engine light might seem like a dashboard light whose only purpose is to cause a sinking feeling in your stomach. While this anxiety-inducing indicator is an unwelcomed sign for many motorists, there are a ton of reasons your car might light the check engine light. Many times, it’s a warning that you should check a relatively minor problem before it becomes a major concern.

Let’s look at the most common reasons a vehicle might detect a problem and ignite that little orange engine.

Loose Fuel Cap

This is one of the most common reasons a check engine light gets triggered. Usually a quick fix, you’ll likely need to simply pull over and tighten your cap – or retrieve it from the roof after pulling out of the gas station. If this doesn’t help, you might need to invest in a new gas cap. A universal fuel cap should only put you back $10-$20.

O2 Sensor Failure

An O2 sensor measures the amount of unburnt oxygen in your exhaust system. The data received from this sensor helps your vehicle’s computer regulate the mixture of air and fuel that enters the cylinders. In the short term, your car will continue to run with a bad O2 sensor but will burn more fuel than usual. Long term – a bad O2 sensor can damage your car’s components and cause it to fail an emissions test.

Catalytic Converter Failure

The role of your car’s catalytic converter is not to turn your car into a heavier, more expensive car (just kidding, Caddy fans), it’s a component integrated into your exhaust system. Its job is to process carbon monoxide into carbon dioxide. Besides your check engine light, you’ll likely notice strange (sometimes very loud) sounds and smoke emitting from your car. Regular maintenance is important in keeping this part in good working order, such as on-time oil changes. If your car is mostly used for short-distance driving, take it out on the highway every once in a while. This helps prevent the catalytic converter from getting clogged.

Spark Plug Issues

Worn out spark plugs can cause many engine issues, like misfires or acceleration hesitation. You might also have issues with your ignition coil (or coils – newer models have one for every cylinder). An ignition coil generates the electricity the spark plugs need to ignite the fuel and air mixture in the cylinders. Lastly, you might have an issue with the spark plug wires. A spark plug wire transfers electricity from the coil to the spark plug. Without it, the fuel and air mixture in the cylinders wouldn’t ignite. Typically, you’ll have one spark plug wire per cylinder, though some cars have two. Common symptoms of spark plug issues include a rough idle, less engine power or performance, and a drop in gas mileage.

A Dying Battery

Yes, a battery that is reaching the end of its lifespan can sometimes trigger your check engine light. Though, if the problem is that none of your lights come on… it’s definitely dead. This is one issue that your check engine light might try to warn you of in advance, but you can’t help but notice when it completely gives out.

People tend to ignore the check engine light on their dash because they fear the issue this light is trying to warn them about will be expensive to fix. The truth is, ignoring the light is often much more expensive than just taking it to a trusted mechanic and getting it resolved.

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