Why Is My Check Engine Light On? Common Causes and What to Do Next
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"Why is my check engine light on?" This is a more common question with older cars, but it's potentially even more alarming if it turns on in a new car. From relatively minor concerns like a loose gas cap to serious mechanical issues, a check engine light can indicate a wide variety of problems. The key is not to panic, assess the situation, and keep your wits about you. Here's what to do when the check engine light comes on.
Understanding the Check Engine Light
A check engine light, sometimes called a malfunction indicator lamp (MIL), is a warning light on your car's dashboard that indicates a potential problem with the car's engine or emission system. It's a signal that something isn't functioning as it should and that you should bring the car to a professional mechanic to diagnose and repair the problem.
Common Reasons for the Check Engine Light To Turn On
A check engine line can turn on for a wide variety of reasons, making it a source of stress for drivers. Even if your check engine light came on while you're on the highway, the cause might be as simple as a loose gas cap. There are many instances in which a check engine light is on but the car runs fine.
Some of the most common reasons this warning light may turn on include:
- Loose gas cap
- Faulty oxygen sensor
- Malfunctioning spark plugs or ignition coils
- Issues with the mass airflow sensor
- Failing catalytic converter
- General issue with the emissions system
It's important to note that a check engine light doesn't necessarily indicate an engine failure. Anything that impacts an engine's fuel efficiency may turn the check engine light on. It doesn't necessarily mean you need to rush off the road to a repair shop immediately.
What Do Different Check Engine Light Statuses Mean?
A check engine light can signify a minor problem. However, it can also be more serious. Typically, a car's check engine light has two statuses: steady and flashing. A steady light indicates a minor problem that the car can drive on for a while, such as a loose gas cap, but should still be addressed soon. A flashing light indicates a potentially severe issue that may cause engine damage if you continue to drive.
When To Address the Check Engine Light Immediately
If your check engine light is flashing, you need to address the issue immediately. If possible, find the nearest professional mechanic and go there immediately.
If you're on the highway, pull over as soon as it becomes safe to do so before a problem becomes so severe as to cause an engine misfire. You can assess a problem yourself once you're safely on the side of the road. If you can't self-diagnose, you should call a mechanic. (It's a great idea to include roadside assistance in your car insurance or dealer warranty.)
Step-by-Step Troubleshooting Guide for Minor Problems
A steady engine light usually indicates minor problems that you can resolve yourself. If you're wondering why your check engine light is on, you can do a quick troubleshoot yourself:
- First, make sure you're parked in a safe place.
- Make sure the gas cap is securely tightened — this is a common cause for the check engine light.
- Ensure there is no smoke coming from the car's hood.
- If you can't readily identify a problem, it's time to take the car to a professional mechanic.
When To Consult a Mechanic: Knowing When It's Beyond DIY
Most cars today have computerized systems that produce error codes when the check engine light comes on. However, you'll typically need specialized equipment to read the codes. If you can't readily identify an issue and make the light turn off yourself, it's time to take the car to a mechanic for diagnosis.
From issues with the combustion chamber to faulty spark plug wires and vacuum leaks, there are many potential check engine light issues that you're not going to be able to solve yourself. (Unless, of course, you're a mechanic in your own right!) It's crucial to know your limits so you don't accidentally exacerbate existing problems.
Preventative Maintenance Tips To Keep Your Car Running Smoothly
Regular maintenance helps avoid issues related to engine speed, performance, and efficiency. Good tips to avoid the check engine light and other issues include:
- Inspecting your tires when you gas up and getting them rotated every 5,000 to 10,000 miles
- Changing your oil every 3,000 to 5,000 miles
- Checking your engine's air filter annually
- Inspecting your brakes every six months
- Inspecting engine belts and hoses whenever you get an oil change
- Replace lights as soon as one dies
Stay Protected: Get the Right Car Insurance Today
When the check engine light comes on, it may mean you're in line for an expensive repair. That's one reason why it's vital to have sufficient car insurance coverage. Find the right plan for your budget by using EverQuote's comparison tools and keep your car and yourself protected.