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Why Is My Check Engine Light On?

Why Is My Check Engine Light On?

When your car’s check engine light comes on, it is usually accompanied by a feeling of frustration and fear of the unknown. The indicator is a subtle way to warn you that there is something wrong with the engine, and you will have to figure out what it is.

Now, the light could mean anything. It could indicate a minor issue, such as a faulty or loose gas cap, or something more significant and serious, such as a misfiring engine. In most cases, the light means that you will have to visit a car repair shop ultimately to fix the issue and get the light turned off.

Some people will ignore the light until other, more visible signs start to show up. This way, they can detect the main problem quite easily. However, that is not a good practice as you are allowing minor car problems to turn into bigger ones during this time.

The following are the most common reasons why your check engine light comes on;

Oxygen Sensor Failing

Oxygen sensors control emissions and ensure that the engine keeps functioning at optimal efficiency levels. It basically measures the amount of unburnt oxygen in the car’s exhaust system. The vehicles use this data to regulate the mixture of air and fuel entering the tank.

O2 sensors continuously monitor gasses entering and leaving the engine. For efficient performance, an engine needs exact ratios of air and fuel. Problems in the sensor lower the fuel economy significantly and also negatively impact the operations of the engine. A bad O2 sensor can also damage components like the spark plugs and the catalytic converter in the long run.

Loose Gas Cap

A loose or faulty gas cap, also known as a fuel filler cap, is one of the most common reasons behind a turned on check engine light. The gas cap is a critical part of a car’s fuel delivery system and controls gasoline fumes from leaving the fuel tank. The gas cap helps keep the whole system under accurate pressure.

If your engine light comes on immediately after a fill-up, pull over and make sure the lid is not loose. Sometimes the cap becomes faulty and needs replacement.

Catalytic Converter

Every car that runs on gasoline has a catalytic converter. It is present in a vehicle’s exhaust system and turns carbon monoxide to carbon dioxide during the combustion process. Its failure can be prevented, and the part is pretty easy to maintain.

Regular maintenance (such as regular oil change) done on time is the most critical thing to keeping your car’s catalytic converter in working order. If you live in the city and drive short distances only, take your vehicle on the highway every once in a while to ensure the catalytic converter does not get clogged. A faulty converter will result in strange noises and discoloured smoke coming out from the exhaust pipe.

Spark Plug Or Ignition Coil Issues

Ignition coils and spark plugs are a critical part of a vehicle’s electrical system. An ignition coil creates the spark needed to ignite the fuel and air mixture in the tank. A malfunctioning coil or spark plug will almost immediately trigger the check engine light.

Signs of issues with coils and spark plugs include engine misfire, hesitation under heavy acceleration, a noticeable drop in engine performance, irregular engine power, including power surges and power losses. Overlooking plug wire and spark plug issues can perpetually damage your vehicle’s catalytic converter, leading to very costly repairs.

Mass Airflow Sensor

The mass airflow sensor (MAF) keeps a check on how much air enters the engine. It is part of an engines’ management system, so the car cannot adjust to changes in altitude without it. MAF failure can cause various issues, including rough engine idling, trouble starting, and a sudden change in the position of the throttle pedal. Decreased gas mileage can also indicate a mass airflow sensor problem.

About Action Towing

At Action Towing, we encourage safe and secure driving, but we are also aware that things can easily go wrong when it comes to not-so-trustworthy vehicles. For emergency roadside assistance or towing services in Edmonton and surrounding areas, call us right now at 780-340-0999 or visit our website for more information.


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