Check Engine Light Flashing When Accelerating

Eagle's Garage may collect a share of sales or other compensation from the links on this page. This comes at no additional cost to you, and all the prices and availability are accurate at the time of publishing.

A check engine light’s job is to alert drivers of potential engine problems. So, if your check engine light is flashing when you accelerate, it means that there’s a problem with your engine.

Normally, we see the check engine light flashing while accelerating, it’s a warning sign that something is wrong with the vehicle’s emission control system. The problem could be as simple as a loose gas cap, or it could be something more serious like a faulty catalytic converter. If you see your check engine light flashing, it’s important to have the problem diagnosed and fixed as soon as possible. 

Not only could you be violating emissions regulations, but you could also be putting your engine’s and your own safety at risk. So if you see your check engine light flashing, take it to a mechanic right away and find out what’s wrong.

What is Check Engine Light?

check engine light blinking
Image: Wikiuser100000, CC BY-SA 3.0, via Wikimedia Commons

So, you might be wondering – what is this little light on my dashboard? In short, the check engine light is an indicator that something is wrong with your car. It could be a simple problem, like a loose gas cap, or it could be a more serious issue, like a faulty oxygen sensor. 

The check engine light comes on when your car’s computer detects a problem. It’ll stay on until the issue is resolved. There are multiple sensors in your car that constantly monitor things like engine speed, exhaust gas composition, and oil pressure. When one of these sensors detects a problem, it triggers the check engine light. 

Also Read: Why Is My Car Sputters When Accelerating

What Does it Mean When Check Engine Light is Flashing?

Normally, you will find that the check engine light is just on – it’s not flashing. However, if the light starts flashing, that means there’s a more serious problem. 

When your vehicle’s Check Engine Light comes on, it does so in three primary ways:

  • Permanent Illumination (the light is on)
  • Intermittent Illumination (the light flashes for a few seconds and then goes out)
  • Consistent Flashing (The light is flashing on and off in an uninterrupted pattern.)

For the first two situations, an emergency does not exist, and you have time to get it fixed before taking it to a mechanic. But for the third case, an emergency definitely exists, and you should pull over to the side of the road and stop driving.

There might be various reasons behind it, but the most common reason is Ignition Misfire on one or several cylinders. 

Common Reasons Why Check Engine Light is Flashing?

There are many reasons why the check engine light might be flashing, but some of the more common ones are:

Loose Gas Cap

check engine light loose gas cap

Yes, it can as simple as that. If your gas cap isn’t on tight, the check engine light will come on. This is because the car’s computer thinks there’s a leak in the system. To fix it, just put the gas cap back on and tighten it up.

Having a open or loose gas cap can be very serious. It can cause your car to not run properly and even damage the engine. So make sure to tighten your gas cap every time you fuel up.

Also Read: How to Test a Gas Cap for Leaks

Faulty Catalytic Converter

AUTOSAVER88 ATCC0007 2.5" Inlet/Outlet Universal Catalytic Converter with O2 Port (EPA Compliant)

A faulty catalytic converter is another common reason for the check engine light to come on. It’s job is to reduce harmful emissions from the car, so when it’s not working properly, it can trigger the check engine light. 

It works by converting pollutants into less harmful emissions. But when the converter isn’t working properly, it can cause the car to produce more emissions than normal. This can be harmful to the environment and also cause your car to run poorly.

Also Read: How to Clean a Catalytic Converter Without Removing It

Faulty Oxygen Sensor

Denso 234-9005 Oxygen Sensor

The oxygen sensor plays a key role in the car’s emission control system. It monitors the amount of oxygen in the exhaust and adjusts the air/fuel mixture accordingly. When the oxygen sensor is faulty, it can cause the check engine light to come on. 

A faulty oxygen sensor can also cause your car to run poorly and damage the catalytic converter. So it’s important to get it fixed as soon as possible.

Faulty Airflow Sensor

FAERSI Mass Air Flow Sensor Meter MAF 22680-7S000 AF10141 for Nissan 2003-2014 Altima & 2006-14 Maxima & 07-13 Sentra & 05-15 Xterra & 2003-2015 Murano | Infiniti 08-13 G37 & 05-08 G35 & More Suzuki

Another important sensor in the emission control system is the airflow sensor. It measures the amount of air that’s entering the engine. When it’s not working properly, it can trigger the check engine light. 

A faulty airflow sensor can cause your car to run lean (too much air and not enough fuel) or rich (too much fuel and not enough air). Either way, it can damage the engine. So it’s important to get it fixed as soon as possible.

Spark Plug/Ignition Issue

ACDelco CR43TS 5614029 (05614029) Professional Conventional Spark Plug BOX OF 8

Last but certainly not least is a spark plug or ignition issue. If there’s a problem with the spark plugs, ignition coils, or wires, it can cause the check engine light to come on. 

Spark plugs are responsible for igniting the air/fuel mixture in the engine. So if they’re not working properly, it can cause all sorts of problems. Ignition coils boost the voltage to the spark plugs, so if they’re not working properly, it can also cause problems. And finally, spark plug wires carry the voltage from the ignition coil to the spark plugs. If they’re worn out or damaged, it can cause a loss of voltage and trigger the check engine light. 

What To Do If Check Engine Light Flashes When Accelerating?

If the check engine light is flashing, you should pull over and have your car towed to a mechanic. Ignoring a flashing check engine light can result in serious damage to your car. So, if your check engine light starts flashing, don’t ignore it! Pull over and try the following checks to see if all is in order or contact a tow truck to take your car in for some professional help. Better to be safe than sorry.

Why You Shouldn’t Drive a Car When Check Engine Light Flashes?

engine light flashing when accelerating driving a car

Driving a car with a flashing check engine light can do serious damage to the car. In some cases, it can cause the engine to seize up entirely which is when the engine won’t start at all. When this happens, the car will have to be towed to the nearest service station and repaired which can be costly. 

So, even if it means waiting a little longer for a tow truck, don’t try to drive your car when the check engine light is flashing. It’s just not worth the risk. Pullover and do your absolute best to get the car to a mechanic.

Related codes:

How Much Does It Cost to Fix Flashing Check Engine Light Issue? 

This largely depends on the problem. If it’s something simple, like a loose gas cap, replacing it might just cost you a few dollars to fix. However, if the problem is more serious, like a faulty oxygen sensor, it could end up costing you a couple of hundred dollars to fix. 

On average, expect to pay anywhere from $100 to $1,000 to fix a flashing check engine light. Once again, it all depends on the problem.

Of course, the best way to know for sure is to take your car to a mechanic and have them diagnose the problem. They’ll be able to tell you exactly what’s wrong and how much it’ll cost to fix it.

Conclusion

The check engine light is an important part of your car’s safety system. It comes on when there’s a problem with your car, and it should be taken seriously. If the check engine light is flashing, that means there’s a more serious problem. In most cases, it refers to an issue with the vehicle’s emissions control system. There are a number of different things that can cause the check engine light to come on, including a loose gas cap, faulty oxygen sensor, or spark plug issue.

Ignoring a flashing check engine light can result in serious damage to your car. So, if your check engine light start flashing, don’t ignore it! Pull over and try the following checks to see if all is in order or contact a tow truck to take your car in for some professional help. Better to be safe than sorry.

If this helped you learn why check engine is light flashing when accelerating, consider checking out our other articles below —

Leave a Comment

Our Best Content In Your Inbox