While most dashboard indicator lights have clear meanings, the check engine light is one of the few that can have multiple interpretations. For that reason, it’s one of the most misunderstood dashboard lights out there.
Since it has multiple meanings, it also lights up frequently. However, in some cases, you may notice that the light is blinking, so why does it do this?
Check engine lights will blink when something serious is going on with your car, especially when your car is misfiring. This can happen for multiple reasons, and in today’s guide, we’ll walk you through each one of them and what you should do about it.
Difference Between Check Engine Steady Light and Blinking
As previously established, check engine light can mean a wide variety of things. And luckily, many of them can be easily fixed without replacing expensive parts.
That being said, you should also know that check engine light can illuminate in two different modes, which have different interpretations.
The first mode is keeping a steady light on. If you see this, it’s usually a warning that something is wrong with your vehicle and might need fixing soon after.
On the other hand, if you see the engine light blinking on and off, it usually means something has already gone wrong or requires immediate attention.
Blinking check engine light can happen suddenly or as an elevation from a steady light. In both cases, you’ll need to power off your engine and have your car checked.
Problems Associated with Blinking Check Engine Light
When the check engine light comes on, you’ll typically notice that your car is functioning normally.
This is because it could be a sign of something minor, such as problems with sensors and other non-critical parts. Yet, you still need to check the car at an auto shop as quickly as possible.
However, when the check engine light is blinking, it’s usually associated with noticeable functioning issues, such as jerky acceleration, strange engine noises, vibrations, and losing power.
That’s why you immediately need to take the car to a qualified service center when you see the light.
What Causes the Check Engine Light to Start Blinking?
The most common cause for the check engine light to start blinking is an engine misfire. This means that fuel combustion isn’t working properly, which leads to fuel reaching the exhaust system unburned, which can cause serious damage to various parts of the car.
Fuel combustion is a complex process that includes multiple parts, and a fault in any of these parts can lead to an engine misfire, so let’s have a quick look at them:
1. Faulty Spark Plugs and Ignition Coils
The first thing you need to check when you suspect an engine misfire is your spark plugs. These are parts that provide the electric spark necessary to initiate the combustion process to put the pistons in motion.
On the other hand, the ignition coil is the part responsible for converting low voltage current into high one to create a spark.
With time, these parts become prone to damage and wear that prevents them from working properly. Luckily, however, a mechanic can easily replace either of them if they stopped working.
2. Fuel System Issues
Another system that can cause misfires when it doesn’t work properly is the fuel system. This can happen for a variety of reasons, such as low fuel pressure.
The fuel system is responsible for adjusting the fuel mixture to create an adequate pressure level in the combustion chamber.
However, any form of compromise to this process can affect the fuel pressure. This includes dirty fuel injectors, clogged fuel filters, or leaks in the fuel line. Other issues that can affect the pressure might include damaged head gaskets or piston rings.
One of the telltale signs that your car has a low fuel pressure is poor or jerky acceleration as there isn’t enough combustion to sustain faster piston action.
3. Timing Belt Issue
This one is a belt or a chain used to synchronize the performance of the crankshaft with the camshaft. As a result, any issues here can massively affect the combustion process and cause misfires.
Similar to fuel system issues, faulty timing belts can lead to poor engine performance. However, you can identify it by a few extra symptoms, including ticking/whirring noise coming from the engine and/or smoke coming out of the exhaust.
4. Air Intake Problem
The air intake system is responsible for maintaining a balanced air/fuel ratio during the compulsion process.
A loose connection or a leak in the air intake system can cause the engine to receive too much or too little air, disrupting the balance inside the cylinders, which leads to misfires. A clogged or dirty air filter can also affect that balance, causing the same problem.
5. Engine Sensors
If none of the previous problems caused a misfire, it could be a result of a faulty engine sensor.
These sensors are easily checked with code scanners in the auto shop, where they can be either reset or replaced if they’re not working properly.
What to Do When Check Engine Light Starts Flashing?
A flashing check engine light is an indicator of a serious problem that you shouldn’t ignore. This is because engine misfires can lead to further damage to various expensive car parts, such as the catalytic converter.
If your car’s check engine light starts flashing, you’ll need to pull over to a safe location and shut off the engine as soon as possible.
Avoid trying to diagnose the problem yourself or use an OBD scanner to clear the code or reset the light. Instead, you should have the car towed to a mechanic to identify the problem and replace the faulty part(s).
There you have it! A brief guide that explains all the different factors that could lead the check engine light to start flashing. This issue is almost always a result of a misfiring engine, so you should never ignore it and keep driving.