If you’re a car owner, you’re probably familiar with the pit you get in your stomach when you see the infamous check engine light turn on. Unfortunately, while we may be tempted to ignore it, that can lead to costly repairs or even a damaged engine down the road. The check engine light is an important part of your vehicle’s onboard diagnostics system. When this light turns on, it means something is not working correctly in your car’s engine or emission control system. Therefore, it’s important for drivers to learn what it means when the check engine light turns on and when to visit a mechanic. 

What Causes the Check Engine Light to Turn On? 

When the dreaded check engine light turns on, it means that your vehicle’s computer system detected a problem with one or more of the components that make up your car’s engine or emission system. While you may be tempted to start panicking, it’s worth noting that the check engine light can turn on for a variety of reasons, and not all of them are worse-case scenarios. For example, it could be a loose gas cap or a minor issue with your engine that’s easily fixable. However, it’s still important to investigate the problem so you can find a solution. 

Possible Reasons for the Check Engine Light Turning On

There are many possible reasons why your check engine light turns on. Some of the most common reasons include: 

  • Faulty oxygen sensor. Your car’s oxygen sensor measures the amount of oxygen in the exhaust and sends the information to your car’s computer. A faulty oxygen sensor can cause a decrease in fuel economy and an increase in emissions, so your OBD system turns your check engine light on when it detects a problem with it. Think of it as your car’s way of saving you money in the long run!
  • Loose or damaged gas cap. If the gas cap is damaged or doesn’t fit properly, dirt and debris can enter your vehicle, fuel vapors can escape, and the emissions system can report an error to your car’s computer, triggering the check engine light.
  • Malfunctioning mass airflow sensor. The mass airflow sensor measures the amount of air entering the engine and helps determine the correct fuel-to-air ratio. Problems with your mass airflow sensor can decrease fuel economy and increase emissions. Like a faulty oxygen sensor, this can cause your check engine light to turn on.
  • Faulty spark plugs. Spark plugs ignite the air/fuel mixture in the engine, so it’s important that they’re operating in top shape. Faulty spark plugs can cause misfires, reduced power, poor fuel economy, and a visit from the check engine light.
  • Broken catalytic converter. This important piece of machinery reduces harmful emissions by converting them into safer gases. If it breaks, your engine’s performance can take a hit and start emitting dark exhaust smoke with a funny odor. To prevent this, your check engine light will activate on your dashboard if it senses a gas leak or a damaged converter.  

Can I Ignore the Check Engine Light? 

Ignoring the check engine light can have negative consequences for your vehicle. Like any mechanical problem, the sooner it’s addressed, the less time it has to snowball into a more expensive problem. Even if the issue seems minor, your vehicle and your wallet will thank you for bringing it to a qualified mechanic if needed. A minor issue could be a symptom of a more significant problem and catching it early can save you a lot of money. 

Additionally, if the check engine light is on, it could cause your car to fail its emissions test, which you need to pass in order to drive legally and register your vehicle in some states.  

When to Visit a Repair Shop

If your check engine light turns on, experts recommend taking your car to a qualified mechanic as soon as possible. During the visit, your repair person will check your computer’s OBD system to find and fix the issue that turned the check engine light on. 

If the check engine light is flashing, instead of just staying on, it means there’s a severe problem with your car’s engine or emission control system. For your safety, stop driving your car and have it towed to a repair shop immediately. Look for a repair shop that specializes in your car’s make and model and has a good reputation for quality work and customer service. If you have roadside assistance, this is a great time to take advantage of it.  

If your check engine light turns on because of a covered incident, you’ll need a quality insurance policy to help cover the cost of repairs. That’s where The General comes in. Check out our affordable rates when you get a car insurance quote in under two minutes or read more on our insurance blog.