It’s a sight that absolutely no driver ever wants to see: the “Check Engine” light blinking. Why does this alert so fill us with dread? The main reason is that there are so many potential reasons for the light coming on in the first place. The fear that we feel is all the possible scenarios racing through our minds until we just get tired and worried, settling our focus on the worst-case scenarios:
- Something it terrible wrong, I need a new engine
- This is going to cost me thousands in repairs and maintenance
- My car is going to break down at any moment
- I’ve done something terrible to the car, what was it? Did I put the wrong fuel in?!
And so, the question persists, why is my check engine light blinking? What should I do about it? These are the core questions that we will answer in today’s blog.
Why is My “Check Engine” Light Blinking?
The unwelcome appearance of your check engine light could mean a number of things. Any of the following things (or even something else could have caused it):
- Oxygen sensor failure
- Spark plug problems
- A vacuum hose leak
- Loose gas cap
There is something of a difference, however, between these circumstances and the times when you have a “Check Engine” light blinking. In the above circumstances, it would normally be a steady “Check Engine” light. When it’s blinking, however, the most likely culprit is an engine misfire leading to potential damage to your catalytic converter.
Related: How to unlock your steering wheel
What is an Engine Misfire?
An engine misfire means when the fuel system dumps unburned fuel into the exhaust system and it doesn’t fire it as it should. It might not sound like such a big deal to the untrained ear, but in fact engine misfiring can massively increase the internal temperature of the catalytic converter, and that is a serious issue.
In fact, any kind of blinking in the “Check Engine” light means that it’s the catalytic converter in particular that is under threat of being damaged.
Why Does the Engine Misfire?
There are three main reasons for the engine misfiring, all of which will most likely need the professional attention of a mechanic. These causes are defects in three key areas of your engine systems: the ignition system, the fuel system or the internal engine.
Ignition systems are fairly easy to fix, and may require a basic replacement of cheap parts. Fuel system defects will cost more to fix because they involve the potential replacement of more expensive parts such as the fuel injectors.
Finally, the internal engine is definitely the one that you don’t want to fix, because the potential damage caused by such a defect could be very serious. These problems can sometimes even start engine fires, damage from which could be catastrophic.
It Gets Worse - “Check Engine” Light Blinking, Car Shaking
What is to be done when the check engine light is blinking and the car is shaking, too? This is one of the scarier scenarios in which we see the blinking check engine light. Once again, the blinking indicates that whatever is happening is much more serious, and potentially threatening to the all-important catalytic converter.
When you are experiencing the “Check Engine” light blinking, car shaking, and the fears that come with it, the most likely reason is a damaged or malfunctioning cylinder in the engine. The cylinders’ job is to pass fuel-air mixture in the system, but if one is malfunctioning, then it upsets the harmony of the entire engine. The result will be a rough, shaky ride that is very unsettling indeed.
Why Would the Cylinder Malfunction?
One possible reason for your cylinder function and resulting “Check Engine” light blinking is that the spark plugs are worn and in need of changing. If you’ve driven more than 100,000 miles since your previous (or first) spark plug change, then it is more than likely that a change of spark plugs is due. Another possibility is that you need new coils.
Your engine coils produce the spark that fires the cylinder as the crankshaft turns. A good mechanic will know to check the coils when you report this “Check Engine” light blinking and car shaking.
Related: How long does an oil change take?
There are two other possibilities, too, the first of which is that you have a faulty intake manifold gasket. A faulty gasket means that the system is not sealed properly, which in turn causes the engine to overheat. You might also smell your car’s coolant if it’s the gasket that’s the problem. The second thing that could be causing your “Check Engine” light blinking and car shaking is a broken engine mount. This is what keeps the engine attached to your car’s frame. If it breaks, then your whole car will shake.
What Should I Do When I See My “Check Engine” Light Blinking?
Seeing the “Check Engine” light in itself is no reason to panic. It doesn’t mean that anything catastrophic has already happened. The system is designed as a kind of early warning mechanism that alerts you to call on the professional attention of a mechanic. In doing so, you will prevent that kind of disastrous engine failure that could happen if you ignore it.
Remember the important rules of thumb:
- Steady engine light means something might be wrong, but it’s not an emergency
- Blinking engine light means the engine needs professional attention immediately
- Any engine light should warrant investigation, steady or blinking.
The main difference is that when you have a steady light, you can probably just find a convenient time when you’re free to take the car to the auto shop. A blinking light, on the other hand, suggests that you should cease any driving unless you’re slowly and carefully making your way to the auto shop in a way that won’t aggravate the potential problems
Ideally, if you have a blinking “Check Engine” light, then you’ll call up roadside assistance or a mobile mechanic to come take a look at the car at home or wherever you are. They can ascertain the main reason and determine if it’s safe to drive to the auto shop or if you might need to get a tow truck. If the tow truck is necessary, don’t balk.
Driving your car with the “Check Engine” light blinking could be a recipe for a seriously expensive repair bill, one that will make the two charges seem insignificant when it might just contain any engine problems within the “minor” bracket.
Conclusion: Never Ignore, but Never Panic
The final thing to remember is that no kind of “Check Engine” light is a warrant to panic. All you have to do is minimize or stop using the car until you can figure out the exact cause and get the quality maintenance that you need.