What Could Cause the Check Engine Light to Come On?

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Witnessing the check engine light illuminate is enough to instill fear in any driver. When the check engine light illuminates, it can indicate minor or major issues with your vehicle.

Service Engine Light vs. Check Engine Light

It’s common for drivers to mistake their car’s service engine light for the check engine light. The service engine light lets drivers know their car needs to be serviced for routine maintenance, including oil changes and other routine car care. The check engine light notifies drivers that trouble is ahead.

Common Culprits of the Check Engine Light Turning On

The check engine light turns on for various reasons. Determining some issues is easier than others.

Loose Gas Cap

A loose or faulty gas cap is one of the most common reasons a check engine light appears. Luckily, it’s easy to fix and won’t cost a fortune to fix like other car repairs. A car’s gas cap helps keep the car running correctly by maintaining the appropriate pressure in the fuel line. To fix a loose or damaged fuel cap, remove it and screw it securely into place. If the fuel cap needs to be replaced, go to an auto part store or order a replacement cap according to the vehicle’s make and model.

Faulty Oxygen Sensor

The oxygen sensor measures the oxygen levels, O2, in a car’s exhaust system. The information the oxygen sensor collects is sent to the car’s computer. This car computer makes the necessary adjustments to maintain the proper mixture of air and fuel.

When the oxygen sensor malfunctions, a car’s engine will idle improperly and compromise the driving experience. Replacing the sensor can be a costly repair, but it’s a quick and easy solution. Neglecting to replace a faulty oxygen sensor can result in damaged engine parts and a less efficient engine and a more expensive problem.

Malfunctioning Catalytic Converter

The catalytic converter turns carbon monoxide the engine creates into carbon dioxide. This converter is located behind the engine. When the catalytic converter malfunctions, a car’s exhaust will reach new toxicity levels, and the car will fail an emission test.

Replacing a catalytic converter is a simple repair for a certified mechanic, but it can be one of many costly repairs. Regular car maintenance can keep a car’s exhaust system running smoothly and be less toxic to the driver and everyone around.

Regularly scheduled car maintenance also helps reduce the risk of having to pay for costly repairs and replacement parts.

Spark Plug Issues

If the spark plugs are worn or damaged, it can cause the check engine light to turn on. Faulty spark plugs cause engine misfires and prevent the car from providing a smooth ride. Bad spark plug wires and a faulty ignition coil can also cause the check engine light to appear.

The good news is these auto issues are easy to fix, and these replacement parts are not as expensive as other car parts.

Failing Mass Airflow Sensor

The mass airflow sensor continuously monitors the amount of air that enters your engine. This airflow sensor sends the airflow information to a car’s computer, helping it run more efficiently. When a mass airflow sensor malfunctions, a car’s performance, such as its gas mileage, will decline because the engine is receiving too much or too little air.

Although replacing a mass airflow sensor is simple for a trained mechanic to fix, it can be expensive. Failing to address this problem in a timely manner makes a car run worse over time and can lead to more serious problems.

More Serious Car Issues

A car may have the ability to display specific malfunctions, such as a flashing check engine light and problem indicators that are different colors, such as red or yellow. A blinking or flashing check engine light alerts drivers that their car is experiencing serious issues that can prevent someone from operating a car safely.

A steady illuminated check engine light is a sign there’s a problem with the car, but it’s not detrimental to its overall performance level and functions.

Is it Safe to Operate a Car with the Check Engine Light On?

When a check engine light illuminates in a car, pay attention. No, it is not safe or smart to operate a vehicle when the check engine light is on. A car may continue to function while the engine light is on, but this is temporary.

If the engine light comes on and starts flashing for over six seconds, pull over immediately, as this is an indication of a serious problem.

Regular maintenance improves a car’s longevity and helps prevent expensive and excessive repairs. Cars make various noises, which can indicate a severe or minor problem. Have the car checked out by a mechanic to be on the safe side.