How long can you drive with a check engine light?
The quick takeaway: a steady check engine light usually allows you to drive for a short period to get the car checked, while a flashing light warrants pulling over safely and seeking immediate help. Exact timing depends on the underlying fault and your vehicle’s design.
What the check engine light means
Modern vehicles monitor a wide range of systems under the hood. When the onboard diagnostic system detects a fault, it stores a trouble code and illuminates the Malfunction Indicator Lamp (MIL), commonly called the check engine light. Codes (usually P-codes) can point to issues in the fuel system, ignition, emissions control, sensors, or even the catalytic converter. A steady light does not always indicate imminent danger, but it should be diagnosed soon. A blinking light, by contrast, signals a more serious condition such as a misfire, which can quickly damage the catalytic converter or other components if driven for long distances.
Solid light vs. blinking light: urgency and actions
Before you decide how far to drive, it helps to know whether your light is steady or flashing. The following guidance covers typical scenarios you may encounter.
When the light is solid (steady)
Key steps to take if the check engine light is steady:
- Tighten or reseal the gas cap. A loose or faulty cap is a common cause of a steady light and can take several miles to clear itself after tightening.
- Note any symptoms such as rough idling, reduced power, stalling, poor acceleration, or unusual noises.
- Consider running a courtesy diagnostic scan. Many auto parts stores offer free OBD-II scans and can reveal the trouble code.
- Plan a diagnostic appointment within a few days to a couple of weeks, depending on your mileage, driving needs, and the specific code. If the car runs normally and you don’t notice symptoms, you may continue short trips, but avoid long highway drives or towing until it’s checked.
In most cases, a steady light means you should schedule a service visit soon, but you can continue driving for reasonable trips while you arrange repairs, provided the vehicle behaves normally and there are no other warning signs.
When the light is blinking
If the check engine light flashes, treat it as an urgent issue:
- Pull over safely at the next opportunity and turn off the engine if you detect a misfire, smell fuel, hear abnormal noises, or see overheating.
- Do not continue driving long distances. A flashing light often indicates a misfiring cylinder, which can damage the catalytic converter or other exhaust and engine components quickly.
- Tow or arrange roadside assistance to a repair shop rather than attempting a long trip. If you must drive, keep speeds low and avoid hard acceleration, but still plan to seek service immediately.
- Note any accompanying symptoms or codes you saw, which you can share with the mechanic for faster diagnosis.
Because a flashing light can indicate a serious engine fault, immediate attention is advised to prevent costly damage or safety risks.
Practical steps you can take now
Whether the light is steady or blinking, these actions help you prepare for a safe, timely repair session.
- Check the basics: gas cap, fluid levels, and obvious leaks or smells.
- Run a diagnostic scan to capture the trouble code(s) before visiting a shop. Many auto parts stores offer free scans; save the code and any descriptions.
- Review your driving patterns. If you’re about to take a long trip or tow a trailer, consider postponing until the issue is diagnosed.
- Consult your owner's manual for model-specific guidance on the MIL and any recommended precautions.
Having the code(s) and symptoms documented helps a mechanic diagnose whether the problem is a simple fix (like a loose gas cap) or something that requires more extensive repair.
What to do if you can’t safely drive
Emergency and towing considerations
If you suspect a serious fault—misfiring, engine backfiring, overheating, loss of power, oil or coolant leaks, or any warning indicators in addition to the check engine light—do not drive the vehicle. Arrange roadside assistance or tow it to a trusted repair facility to avoid risking a breakdown or damaging the engine and emissions components.
Summary
In short, a steady check engine light usually means you should schedule diagnostic work soon, but you can typically complete short trips if the car runs normally. A blinking light indicates a more urgent problem that demands immediate attention and usually a tow. The exact safe distance or time before repair varies by fault, vehicle design, and driving conditions. When in doubt, err on the side of caution and seek professional diagnosis to prevent further damage and ensure reliability and safety.
Additional context and resources
If you want to learn more about what your codes mean or find a nearby diagnostic service, check with your carmaker’s official service pages, ASE-certified technicians, or reputable auto repair associations for guidance tailored to your vehicle and location.
Can a check engine light go away by itself?
Yes, a check engine light can clear itself if the underlying issue is resolved, but it won't happen immediately. The light typically goes off after a few driving cycles—where the car is started and driven for a certain distance—if the computer no longer detects the problem. For example, a loose gas cap can trigger the light, and after it's tightened, the light may turn off on its own after some driving.
How it works
- The vehicle's computer monitors various sensors to detect issues.
- A minor or temporary fault, like a loose gas cap, can trigger the light.
- If you fix the problem (e.g., tighten the cap), the computer will continue to monitor the system.
- Once the vehicle has completed a certain number of "drive cycles" (a specific combination of driving and stopping), the computer will recognize the issue is gone and turn the light off automatically.
This video explains how to reset a check engine light using several DIY methods: 1mAuto EducateYouTube · Apr 14, 2025
What to do if the light comes on
- Check the gas cap: This is a very common and easy fix. Remove it and re-tighten it until it clicks. Then, drive for a while to see if the light turns off.
- Drive and wait: If the issue was temporary (e.g., a brief sensor reading out of range), the light may go off on its own after a few days or about 30–50 miles of driving.
- Get the codes read: You can buy an inexpensive OBD-II scanner to read the specific trouble code that is causing the light. Many auto parts stores also offer this service for free. This will tell you exactly what the problem is.
Important note
- If the check engine light comes back on, even after it had gone off, it indicates the problem is still there and needs to be addressed professionally.
- If the light is flashing, it indicates a severe misfire, and you should pull over and have the vehicle towed to a mechanic.
How far can I drive with a check engine light on?
You can typically drive with a steady check engine light for a short distance to a mechanic, but if the light is flashing, you should pull over as soon as it's safe and get the car towed, as this indicates a severe and potentially damaging problem. A steady light often suggests a minor issue like a loose gas cap or oxygen sensor, while a flashing light commonly signals an engine misfire that can quickly cause expensive damage to the catalytic converter.
You can watch this video to learn about the potential causes and risks of a flashing check engine light: 55sAuto V Fix YouTube · Nov 10, 2022
If the light is steady
- Minor issues: A steady light can be caused by minor problems, and you may be able to drive for a while.
- Schedule an appointment: You should get your car checked out as soon as possible to prevent the issue from worsening.
- Avoid heavy driving: Avoid heavy acceleration, high speeds, or towing until you can get it diagnosed.
If the light is flashing
- Serious problem: A flashing light indicates a severe issue, such as an engine misfire, that needs immediate attention.
- Stop driving: Do not continue driving unless absolutely necessary to get to a safe spot to pull over.
- Damage to the catalytic converter: Continuing to drive can cause extensive and costly damage to your catalytic converter.
- Seek immediate assistance: It's best to have the car towed to a mechanic rather than driving it further.
This video explains what to do if you see a flashing check engine light: 53sTorqueCarsYouTube · Apr 24, 2023
What to do immediately
- Check the gas cap: First, ensure the gas cap is on tight, as a loose cap is a common cause for a steady check engine light.
- Monitor for other symptoms: Pay attention to any changes in your car's performance, such as unusual noises, loss of power, or poor fuel economy.
- Consult your manual: Always check your vehicle's user or repair manual for specific safety precautions.
Can I drive my car with a yellow engine light on?
Amber Check Engine Light
An amber light usually means that you are able to continue driving but should have the car checked as soon as possible.
Will AutoZone check engine light for free?
Yes, AutoZone offers a free "Fix Finder" service to scan and diagnose check engine lights. A store employee will use a special tool to read the diagnostic trouble code, which can be found by plugging the tool into your car's port, typically located near the steering wheel. After reading the code, AutoZone will provide a report with possible solutions and recommended parts.
How the free service works
- Visit a store: Go to your nearest AutoZone and let an employee know you need the "Fix Finder" service for your check engine light.
- Code reading: An employee will use a handheld scanner to plug into your car's OBD-II port, which usually takes less than a minute.
- Get a report: The employee will provide you with a report, which can be printed or emailed, detailing the diagnostic code and recommended fixes.
- Potential solutions: The report can provide you with information on potential causes, like a loose gas cap, or more serious issues, giving you a better idea of what the problem might be before you go to a mechanic.
- Light reset: In some cases, the employee may also be able to reset the light after the code is read, especially if the issue is minor.
