Check Engine Light But Car Runs Fine | 100% Fixed

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betti holt`

Check Engine Light But Car Runs Fine: Meaning, Reasons, And More

Among all the chimes, sounds, and lights that your car’s dashboard makes, seeing the car check engine on is surely no one’s favorite. Nobody likes that orange engine-shaped icon; however, this warning indicator should never be ignored.

Basically, the car check engine light is a warning indicator designed to tell the car engine’s condition. There are several small and big reasons why you are seeing these warning signs. It is also possible that the check engine light is one, but the car runs fine.

We have curated a list of all the possible reasons why the car check engine light illuminates. Some minor issues don’t necessarily need professional attention, and you can solve them yourself. Others might need a trip to the service center.

Apart from genuine problems with the car engine, sometimes these warning signs are turned on because of a false alarm and a broken o2 sensor. And often, people tend to ignore the check engine light of that, which is not safe. Don’t be like Penny from the American sitcom ‘The Big Bang Theory”.

Imagine, after a tiring day of work, you’re finally going home to take a sigh of relief, and you see the check engine light is on. Frustrating, right? After having a chaotic day, you decide to ignore it and look at the matter later. Now it’s the next day and another busy day.

This can go on forever…

It is advised to promptly address the arising issue because you might not want to spend half your paycheck on engine repairs later. This way, you can eliminate expected expenses and be safe on the road too.

What Does It Mean If The Car Check Engine Light is On?

An engine is undoubtedly among the major components of a car. They are the heart of the car. Safety should never be compromised, which is why your car has the check engine light and other warning indicators.

Just like a good heart is vital for a healthy human, a good engine is essential to ensure safe rides. Service Engine Soon Light (SES) and Malfunction Indicator Light (MIL) are other names given to check engine light.

To ensure that any malfunction in the car’s engine is detected at an early stage, the car manufacturers install a check engine light. This warning indicator illuminates when the internal diagnostics see any fault in the engine.

The dashboard will turn on the check engine light on the dashboard along with the codes indicating which component of the engine is experiencing trouble. However, if the car check light is on with no codes, it does not mean you should ignore the warning.

9 Common Reasons Why Car Runs Fine But Check Engine Light Is On

Knowing some common reasons why check engine light ignites would be helpful in uncertain situations. Having a service center nearby is not always possible. Hence, knowledge about them is essential for car drivers.

When Engine Overheats

The most apparent reason why check engine light is on could be because the car engine is overheating. There are several reasons why car engines overheat. Oil going bad, a failing water pump and low coolant in the system could be some possible reasons.

An overheating car engine can cause mechanical issues in the car. Several components of the engine, like cams, cam phasers, pistons, etc., get affected by engine overheating. This can cause the check engine light to turn on.

Loose Gas Cap

The gas cap serves as a protective cover for the engine, akin to a bottle cap. It creates an airtight seal that prevents harmful external contaminants from entering the fuel system. A loose gas cap can allow excess air to enter the system, which may cause the check engine light to turn on despite the car running smoothly.

A common cause of the check engine light is a loose or faulty gas cap, which can also result in pressure-related problems in the fuel system.

To resolve this issue, it is advisable to check the gas cap for looseness or damage. Tightening the cap by twisting it or replacing it if it is damaged are the only solutions. To ensure the gas cap is firmly secured, it should be clicked at least three times.

 Engine Misfire

The car engine can misfire for many reasons; vacuum leaks, issues in the fuel injector, bad spark plugs, or ignition coil. A misfired engine indicates that the combustion process inside the engine cylinder is disturbed. This is a serious issue and needs immediate attention.

The spark plug and ignition coil work together in the fuel combustion process. An engine will misfire if any of these parts get damaged. Another common reason for engine misfires could be issued with the fuel injector. Fuel combustion would not happen properly if the fuel injector malfunctions.

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Malfunctioning Diagnostics

The car engine check light can be turned on because of a false alarm sent by the system. The system can sometimes detect a fault that doesn’t exist, pointing out that the car’s internal diagnostic system is malfunctioning.

Ignoring these false alarms and thinking that there’s nothing serious can be dangerous. Under these false alarms, it is possible that your car is experiencing other issues. Hence, getting the car checked is advised so that the system can accurately detect malfunctions.

Catalytic Converter

The proper functioning of the catalytic converter is essential for your car to pass specific tests. The catalytic converter turns the carbon monoxide the car produces into carbon dioxide.

This is not only important for the car but also for our environment. With the increasing amount of pollution and the number of cars on the road, we must reduce the damage as much as possible.

The car can experience overheating and low fuel economy if the catalytic converters do not work correctly. Hence, the converter’s presence and proper functioning are necessary to have your car pass the vehicle emission test.

Clogged Air Filter

The main purpose of the air filter is to act as a barrier between the system and the outside dirt and dust. You must replace the engine air filters frequently.

It’s the same way the water filters at our home works. The cleaners use filters to capture the toxins and impurities so that we can get clean water. Similarly, the engine air filter helps provide clean and pure air to the car engine.

A clogged engine air filter cannot provide sufficient air to the engine system, so the combustion process gets disturbed. It is advised to replace these filters after every 20-30,000 miles distance the car has covered.

 Dead Battery

Another reason why the check engine light is on could be because the battery is dead. Without a car battery, running a car is not possible.

The battery’s price could differ based on the car you own. Changing them are not very expensive. You can purchase a good quality battery ranging from $100 and above.

Issues In Oxygen Sensor

The oxygen sensors are a significant part of the car’s emission control system. The sensors help measure the oxygen levels in the exhaust and send a signal in case it is low. The system then compares the reference value with the current value of the oxygen level.

The car could have multiple sensors, depending on what car you own. These sensors also measure the air-to-fuel ratio, and a lousy ratio can affect the engine power.

Issues in Mass Airflow Sensor

Any kind of malfunction in the mass airflow sensor will cause the car engine check light to turn on. These sensors are a standard part of most diesel and gasoline engines. This component of the fuel management system can be found between the intake manifold and the air filter.

The main purposes of the mass airflow sensors are to maintain the desired amount of air intake in the engine. With the help of the mass flow rate, these sensors can adjust the air levels in the engine.

In case issues appear in the mass airflow sensors, the dashboard will notify you with a specific code. Check the system for vacuum leaks before deciding to replace these sensors.

Is It Okay to Ignore The Car’s Check Engine Light?

Check engine lights serve as a vital warning system informing drivers of engine malfunctions. However, false alarms can also cause the light to activate, even if the car functions correctly.

Dismissing the check engine light as a false alarm can have significant consequences, including expensive repairs down the line and potential safety risks to oneself and others on the road.

There are various reasons why the check engine light can turn on, ranging from minor issues to more significant engine problems.

As technology advances, warning signals have evolved to include different colors and brightness levels to indicate the problem’s urgency.

Drivers must understand the meaning of each color to avoid further complications. With the aid of car diagnostic equipment, it is now easier to pinpoint the exact cause of the check engine light. However, if the issue appears to be complicated, seeking a professional opinion is always a wise choice.

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Below are the frequently asked questions on car runs fine but check engine light is on. Lets dig deep to know more.

What can I do if my car runs fine but the check engine light is on?

If you have no experience in car repair, the best thing you can do is leave the situation in the hands of a professional. Messing around with things you don’t understand can make the problems worse.

However, if you have worked with cars before, you can do the basic diagnostic check and solve minor problems. Most of the time, along with the check engine light, the engine system also displays a specific trouble code. There are different trouble codes for various problems.

The code readers are readily available at automobile parts stores. All you have to do is plug in the code reader and find the code’s meaning with the help of the guide. The code will tell if the problem in the engine is severe or not.

You can make critical decisions upon finding out the problem and its urgency. Either fix the problem, but only if you are confident, or quickly stop at the shop.

What are those codes shown along with the check engine light?

The car check engine light is designed to display trouble/error codes with them. A specific trouble code indicates different problems in the engine. Identifying the code would let you know the issue and the component needing repair.

However, these codes do not always tell the problem accurately. Sometimes they can be misleading. But with the professional scanner available in the market, you can increase the result accuracy when you scan the code.

If you are not ready to invest in an expensive professional scanner, you can purchase Bluetooth scanners. They are comparatively cheaper, but some do not work in every car model.

What should I do if my check engine light is continuously blinking?

The continuous blinking or on & off of the check engine light means that the car engine is severely damaged. A malfunctioning catalytic converter and an engine misfire can cause this situation.

In this situation, you can turn off the car immediately and take it to the mechanic or service center. You can take the necessary actions to fix the problem upon examination.

What are the other indicators that show problems in the car?

The computer system in the car nowadays comes with different kinds of warning indicators. They differ in color and design. These warning signs will help the driver find possible leakages and malfunctions in the car.

Besides the engine warning light, you will find warning lights for the seat belt, engine temperature, anti-brake locking system, oil pressure, service engine, low fuel, parking brake, tire pressure, and battery charging in the car indicators list.

These are several other indicators, and the drivers can easily learn them with the help of the internet or a guide.

The Takeaway 

The check engine light tells whether the car’s engine is working fine or not. If you see the check engine light is one and is blinking, then immediate action needs to be taken. For instance, the light will keep blinking in case the engine backfires.

That is all I wanted to say on the check engine light but car runs fine. Several other reasons, like the malfunctioning oxygen sensors, dead batteries, bad fuel pressure regulator, and overheating engine, can also cause the check engine light to turn on.

In conclusion, the warning signals like check engine lights should not be left unattended for long, even if the car runs fine.

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betti holt`

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