Why Does Check Engine Light Flashing Then Stops Suddenly?

Every car has an assortment of car warning lights on the dashboard and they all have a different meaning. When any notification appears on your car’s dashboard. It can cause a fair amount of stress, especially if you don’t know how serious the alert may be. Nothing can be more frustrating than when you’re running extremely late for your important office meeting and the check engine light flashing then stops on the dashboard. Now, what is causing this issue? Let’s see it in detail. 

What Does The Check Engine Light Mean?

The check engine light is easily identified. It looks like an engine and typically includes words such as “check.” Usually yellow or red. Its main function is to let you, as the driver, know that one of the car’s sensors is not functioning correctly. The check engine light will either be in a solid unblinking state or flashing. Whenever you start your car you’ll notice that the check engine light glows temporarily usually for around six seconds.

The check engine light is more formally known as the malfunction indicator lamp (MIL). When this light comes on it is a signal from the car’s engine computer that something is wrong. Check engine lights come in orange, yellow, or amber, depending on the manufacturer. If the light begins flashing, however, it indicates a more serious problem, such as a misfire that can quickly overheat the catalytic converter. These emissions devices operate at high temperatures to cut emissions but can pose a fire hazard if faulty.

Why Does Check Engine Light Flashing Then Stops Suddenly?

The check engine light is a type of signal that detects and indicates vehicle malfunctions. It’s an onboard diagnostics system that can find out any defect in ignition, fuel or exhaust systems, or emissions system. Also provides essential and immediate signals to you.

If you notice the check engine light flashing and then stops suddenly you need to stop driving immediately. Otherwise, it may cause serious damage like engine misfires. Check engine light is actually triggered by your car’s computer which is monitoring sensors throughout the system. It will be saying one of the sensors has found something wrong. Just make sure when you are looking at the check engine light, either it is constantly on or flashing continuously.

What Is The Engine Misfire?

To provide the power for the vehicle to be driven, the typical engine of the car needs to have a group of cylinders where the air and fuel mix and ignite.

In other words, if one of the cylinders or more cylinders happened to have an issue and were not able to work properly then the check engine light would start flashing behavior.

Next time or the moment you are going to wonder why your check engine light is flashing then most of the time it might be a misfire of your engine.

What Are The Indications Of Engine Misfire?

You will recognize right away that the car is not doing as well as it usually does if the check engine light is flashing, especially at high RPM (revolution per minute) when the vehicle starts to be jerky or jumpy. The first indication is the sound of the engine, one of the first signals you can immediately notice an engine misfire is the weird sound of the engine of your vehicle.

You can notice that the engine could be driving roughly and jerky which tells you to stop driving and gather some ideas about what is happening. You can also experience check engine light flashing or car sputtering that is being categorized in severe scenarios.

The second indication is the smell of the gas, this must be the most obvious situation you’re going to face if ever happens. Its smell plus a check engine light that is flashing can signal that there is something wrong or leaking in your fuel and issues like this could be severe.

Some other engine misfire indications include difficulty in starting your vehicle, black smoke keeps on coming out of the tailpipe of your vehicle, and a smell like an egg that has been rotted coming out of the exhaust of your vehicle.

What Could Cause Your Check Engine Light To Come On?

The Malfunction Indicator Light (MIL) i.e. check engine light is a warning light (sometimes called a tell-tale) that indicates a malfunction with your vehicle (as detected by your car’s computerized engine-management system). When something goes wrong in this complex collection of components and sensors, it triggers this light. It’s usually displayed on your dashboard as a pictogram or symbol of an engine, or sometimes simply CHECK ENGINE, or CHECK ENGINE SOON.

Most Common Causes For The Check Engine Light To Come On:

1. Faulty Oxygen Sensor:-

The Oxygen Sensor measures the amount of oxygen in your exhaust system. It then communicates this information to your car’s computer so that it can adjust the engine’s air and fuel mixture. When your oxygen sensor is faulty, your car will use up more fuel and produce more emissions by triggering the check engine light to come on.

2. Faulty Gas Cap / Fuel Cap:-

A cracked, faulty, or loose gas cap/fuel cap can cause your engine light to come on mainly because the fuel system has a vapor leak. In other cases, it could be a more serious leak in the upper portion of the fuel system.

3. Failed Catalytic Converter:-

A catalytic converter controls emissions in your car’s exhaust system. It converts carbon monoxide and other harmful gases into less harmful byproducts. If your catalytic converter is failing, it will cause your car check engine light to come on.

4. Faulty Spark Plugs:-

The bad or faulty spark plugs could be another main reason for the check engine light being on.

5. Faulty Mass Airflow (MAF) Sensor:-

The Mass Airflow Sensor or MAF Sensor helps your car’s computer determine the amount of fuel to be added based on the amount of air coming into the motor. A common cause of MAF sensor failures is a dirty air filter or one that’s not properly installed.

Therefore, these are some common reasons for the check engine light flashing then stops glowing on the dashboard. 

Is It Safe To Drive While The Check Engine Light Is On?

If the check engine light is flashing, you can’t keep driving the car. It’s an emergency. Often it indicates an engine misfire. If you keep driving, you will likely cause irreversible damage, mostly to the (expensive) catalytic converter.

Don’t risk that expense – have your car towed to a certified mechanic for repair.

How Do I Diagnose The Misfire Issue?

The check engine light flashes to indicate a chance of misfire. The common reasons behind misfires are clogging spark plugs, vacuum leaks, weak fuel injectors, worn valve seals, no voltage at the coil, carbon tracking, and so on.

Step 1

We need to figure out why the light is on. So you need to read the codes with a code reader. Or do it from auto parts shops that offer to decode free. Once you decode the code, you can diagnose what’s happening to your car. The code reader shows codes for misfires. Also, that shows specific descriptions with cylinder numbers. For example cylinder 2 is misfiring. When you identify the misfire problem, you have to go for the further step.

Step 2

The second step is to remove the spark clog. There are a couple of things you need to check before this step. Is there oil on these threads or above the shaft or remain dry? Oil leaking caused the spark plug problem and led to misfires or blue smoke. If they dry, check the electrode on a spark plug. Then you should replace them with a new spark plug. Because damaged spark plugs are pretty cheap to get them out anyway and often they can have problems internally.

Step 3

The check engine light may not go off on its own. You have to reset it. Before you turn the car on after doing repairs, you have to clean your engine code. So that you will know whether the repair works or not. You can use a code reader. Or you can go under the hood and disconnect the negative terminal to the battery for a minimum of 10 minutes or more. Which will reset the computer and turn the light off.

Therefore, these are some steps to diagnose the reason behind the check engine light flashing then stops glowing on the dashboard. 


We hope the above-mentioned information about the check engine light flashing then stops glowing suddenly will be helpful to all the readers. If anybody’s doubts persist feel free to comment in the comment section below. We’ll try to solve your doubts as soon as possible.

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