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What To Do When Your Car’s Check Engine Light Is On But It Runs Fine?

What To Do When Your Car's Check Engine Light Is On But It Runs Fine

Have you ever been in a situation when you’re driving and randomly the check engine light comes on but the car runs fine? Well, you’re not alone. There are many drivers out there who have faced a similar issue and are often unaware of the possible reasons.

While it may seem alarming, sometimes it may just be a minor issue and have nothing to be worried about. The check engine light can turn on even if it is a small issue like a loose fuel cap.

In this blog, we’ll discuss the reasons why the check engine light might turn on, what those reasons mean, and whether you should be concerned. Understanding the possible causes can help you decide whether it’s safe to keep driving or if it’s time to investigate further.

What is a Check Engine Light?

In simple terms, a check engine light indicates there might be something going on with your engine. The check engine light on your car dashboard can come on for various reasons, including both major and minor issues. Sometimes the light turns up as a reminder for you to check if your car’s engine is working properly.

A check engine light can be still, or it may even be flashing. A solid check engine light usually means there isn’t anything major, and it could be as minor as a loose gas cap or an oxygen sensor malfunction.

A flashing check engine light indicates there is a major issue that needs your immediate attention like an engine misfire or an internal engine issue.

Common Signs of Check Engine Light Coming On

Common Signs of Check Engine Light Coming On

There can be several minor or major issues that cause your check engine light to be on; however, no matter what the issue may be, one should pay attention and have it fixed immediately. Here are the most common reasons for the check engine light to come alive on your dash:

  • Oxygen sensor failure: An oxygen sensor is often found in the exhaust system of your car to measure how much oxygen is there in the exhaust. At times the sensor may have simply been moved or there may have been a simple wiring issue, but it could also be broken.
  • Loose fuel cap: A loose fuel cap can often trigger the check engine light; it simply means the fuel cap needs to be tightened in order to prevent the fumes from escaping.
  • Catalytic converter failure: It is most likely your vehicle’s catalytic converter is not working and may need replacing. This also indicates there is a problem elsewhere that has caused the catalytic converter to fail.
  • Spark plug/ignition coil issues: This issue is only applicable for petrol vehicles. Spark plugs help start the engine by creating a spark, and ignition coils send power to the spark plugs. If either one of them is not working, the check engine light will be turned on, and your engine will also experience trouble starting.
  • An aftermarket alarm: An aftermarket alarm can cause the check engine light to turn on if it’s wired incorrectly or causing electrical problems. It might drain the battery, mess with the car’s sensors, or interfere with other systems, triggering the light. If you notice this happening after installing the alarm, it could be the cause.
  • Dead battery: A dead battery can trigger the check engine light because it affects the car’s electrical system. When the battery isn’t providing enough power, it can cause the car’s sensors or computer to malfunction. This can lead to warning lights, including the check engine light, appearing on the dashboard.

Why Your Car May Seem To Be Running Fine?

Have you ever wondered, ‘Why is my check engine light on, but my car runs fine?’ That’s because it isn’t necessary for your car to shut down immediately as the check engine light turns on. If your ride is operating fine even after the check engine light is illuminating, it is a clear indication it is probably caused by minor issues like a loose fuel cap, which if left unchecked could create major problems down the road.

Such a thing is alarming in older vehicles; however, you do not have to worry much in case of modern vehicles. Modern cars these days have high-end technology and are durable enough to tolerate such issues and can still give you a time period to reach home and check for the underlying issues.

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Whether you own a latest trendy automobile or an older one, we would recommend you look for the cause as soon as possible to avoid any major issues in the future. If you are unable to find the cause or found and handled it but the light won’t go away, take your ride to a professional.

When Should One Be Concerned?

It is okay to delay handling of the minor problems that are causing the check engine light to be on, like a faulty oxygen sensor or a loose fuel cap. These problems don’t really need immediate action and you can go by driving your ride smoothly for quite some time.

However, problems like a faulty catalytic converter or faulty spark plugs can be a major cause of concern as they can lead to serious problems like engine failures.

But as a car owner you must understand that no matter how big or small a problem is, you should never ignore it or put it on hold. The ignorance of your check engine light can cause many severe problems for you down the road, such as:

  • Increased damage over time: One problem will lead to the other, which will also cause you heavy repairs in the future.
  • Decreased fuel efficiency: Ignoring the check engine light can lead to decreased fuel efficiency because some problems, like a bad oxygen sensor or spark plug, can make the engine burn more fuel than necessary. When the car isn’t running as efficiently, it uses more gas to do the same work, causing your fuel economy to drop.
  • Safety concerns: The check engine light may also be turned on due to faulty airbags; it is essential to have all possible outcomes looked at and not sacrifice your own safety.

Step-by-step Guide to Handle Check Engine Light Illumination Issue

Step by step Guide to Handle Check Engine Light Illumination Issue

No matter how small or big the problem with your vehicle may seem, you should always have it checked out and fixed. Ignoring such problems will only lead to even bigger problems like a busted engine.

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The first step to handling the problem is to remain calm; panicking will not get you anywhere. If you are driving and you see a flashing check engine light, immediately pull over and call for help.

Professional Assistance

If you anticipate that your vehicle is suffering from serious problems like engine misfire, faulty catalytic converter, or coolant leaks, you should take it to a professional immediately. Sure, you can go all DIY if you want, but in such scenarios, we recommend having a trained mechanic take a look at your ride.

DIY Handling

If there is a solid check engine light on your dash and you are sure that your vehicle might be suffering from some minor problems, you can save time and money by handling the issue using an OBD-II scanner. In this case too, you can go for the professional assistance, but if you’d like to do it on your own by using an OBD scanner, make sure to follow these steps:

  1. Make sure the vehicle is off before you start.
  2. Locate the OBD-2 port, which is under the driving wheel.
  3. Plug in the OBD-2 scanner and start the ignition of the vehicle.
  4. After your vehicle is on, press scan on the OBD-2 scanner.
  5. You should now have a code on the scanner. Every code is associated with different issue. Read below to find out which code means what.

Codes of Check Engine Light on OBD-II Scanner and What They Mean

An OBD-II scanner can help you run and diagnose your car problems through the error codes displayed on your car’s computer. These codes identify any ongoing problem so you can sort it out at the earliest. Here is a list of common codes that display when the check engine light is on:

  • P0128 – Coolant temperature below thermostat regulating temperature: Low coolant level or faulty coolant temperature sensor.
  • P0300 – Random/multiple cylinder misfire detected: Engine is misfiring due to faulty ignition coils or worn spark plugs.
  • P0401 – Exhaust gas recirculation “A” flow insufficient detected: The EGR is not recirculating the exhaust gases back to the engine.
  • P0420 – Catalyst system efficiency below threshold: The catalytic converter is not working.
  • P0440 – Evaporative emission system: Indicates a loose gas cap or faulty EVAP system.
  • P0442 – Evaporative emission system leak detected (small leak): Cracked or damaged EVAP hoses.

Tips to Avoid Abrupt Check Engine Lights Coming On In The Future

Tips to Avoid Abrupt Check Engine Light Coming On In The Future

As a car owner It is important for you to follow extra care tips to ensure optimal performance of your vehicle and your vehicle’s engine. This can even ensure longevity, and your vehicle will hold over a great resale value. Here are some tips you should definitely follow to avoid check engine lights in the future:

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  • Regular maintenance: Regular services will ensure all the fluids are up to the mark, any underlying problem will be fixed, and if anything else needs fixing or changing.
  • Drive responsibly: harsh driving habits can often stress the engine, leading to shorter lifespans and more problems.
  • Check fuel cap: every time you fuel up, make sure to tightly seal the fuel cap back on.
  • Replace faulty parts: If you happen to notice any faulty part, have it changed immediately and try having it changed with genuine parts.

Frequently Asked Questions

Q1. How long can you ignore the check engine light?

This can depend on the problem that is causing the check engine light. If it is a flashing light, it mustn’t be ignored and should be checked immediately; if it is a solid light, this could mean something minor, and you can wait till you reach home to check it out.

However, the check engine light shouldn’t be ignored, whether they’re minor issues or major issues, as these problems can lead to something worse over time.

Q2. How do you know if a check engine light means something serious?

If it is a flashing check engine light, that indicates something serious. This sort of problem should not be ignored and should be checked out right away by a professional. You can even check the problem yourself by using an OBD-II scanner and then have a mechanic fix it.

Conclusion

This blog covers all the top reasons for why your check engine light comes on, but the car runs fine. In addition to this, it also provides insights on what to do when encountered with an issue along with when you can go for DIY repairs or seek professional assistance in order to avoid bigger problems and heavy repairs.

Following tips mentioned here and having regular services can also prevent problems from occurring and hence avoid the check engine light from coming on in the first place.

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