A check engine light means your vehicle's onboard diagnostic system has detected a potential problem. It could be something minor, such as a loose gas cap, or something that requires immediate attention.
Solid vs. Flashing Check Engine Light
A solid check engine light usually means your vehicle has detected a problem that should be diagnosed. If your vehicle is driving normally, you can typically drive it to a service department, but don't ignore the warning.
A flashing check engine light is more serious. It can indicate an engine misfire or another condition that could cause additional damage. If the light is flashing and your vehicle is shaking, losing power, running poorly, or making unusual noises, pull over safely and have it inspected as soon as possible.
7 Common Reasons Your Check Engine Light Comes On
Some of the most common causes include:
- Loose or damaged gas cap – A loose gas cap can trigger an emissions warning.
- Worn spark plugs – Faulty spark plugs can cause misfires and poor engine performance.
- Oxygen sensor problems – A failing sensor can affect fuel economy and emissions.
- Emissions-system issues – Your vehicle has several components designed to control emissions, and a fault can trigger the light.
- Ignition problems – Issues with ignition coils or related components can cause engine misfires.
- Catalytic converter problems – A failing catalytic converter can affect emissions and vehicle performance.
- Faulty sensors or electrical components – Modern vehicles depend on numerous sensors to monitor engine operation.
Can You Drive With the Check Engine Light On?
If the light is solid and your vehicle is running normally, you can often drive a short distance to have the problem diagnosed. However, continuing to drive indefinitely without finding the cause can turn a small problem into a larger—and potentially more expensive—repair.
If the light is flashing, don't assume it's safe to continue driving. A flashing warning can indicate a serious engine issue.
Nebraska drivers should also consider their driving habits. Long commutes, rural roads, gravel roads, and extended highway trips can make it especially important to address warning lights before you're far from home.
What Should You Do When the Light Comes On?
First, check whether the light is solid or flashing. Then pay attention to how your vehicle is behaving.
If you notice rough idling, shaking, reduced power, poor fuel economy, unusual smells or noises, difficulty starting, or smoke, have the vehicle inspected promptly.
If the vehicle seems to be running normally and the light is solid, schedule a diagnostic check to find out what's causing the warning.
Check Engine Light FAQs
Can a check engine light turn off by itself?
Yes. A temporary issue can sometimes cause the light to turn off, but that doesn't necessarily mean the underlying problem is fixed.
Is the check engine light the same as a maintenance light?
No. A maintenance reminder indicates routine service may be due. A check engine light means the vehicle's diagnostic system has detected a potential problem.
What does a flashing check engine light mean?
It can indicate a serious issue, such as an engine misfire. Have the vehicle inspected promptly.
How long can I drive with the check engine light on?
There is no universal time or mileage limit. It depends on what's causing the light and how the vehicle is performing.
Don't Ignore Your Check Engine Light
A check engine light doesn't always mean an expensive repair, but it's a warning worth taking seriously. Getting the problem diagnosed early can help prevent additional damage and keep your vehicle running reliably.
If your check engine light is on, contact Janssen Auto Group's service team to schedule a diagnostic inspection and find out what your vehicle needs.