What is the most common cause of flashing a check engine light?
The check engine light is one of the most dreaded warnings for drivers. When it starts flashing, it’s a sign that something is seriously wrong with your vehicle. At Kevin's Autos, with years of experience in car maintenance and repair, we’ve seen countless cases of flashing check engine lights. In this article, we’ll explore the most common cause of this issue and what you should do if it happens to you.
Understanding the Check Engine Light
The check engine light is part of your car’s onboard diagnostics system (OBD). It monitors various components of your vehicle, including the engine, transmission, and emissions system. A steady light often indicates a minor issue, but a flashing light is a sign of a severe problem that requires immediate attention.
The Most Common Cause: Misfiring Engine
At Kevin's Autos, we’ve found that the most common cause of a flashing check engine light is an engine misfire. A misfire occurs when one or more cylinders in your engine fail to ignite the air-fuel mixture properly. This can lead to unburned fuel entering the exhaust system, which can damage the catalytic converter—a costly repair.
What Causes an Engine to Misfire?
Several factors can lead to an engine misfire. Here are the most common culprits:
- Faulty Spark Plugs or Ignition Coils: Worn-out spark plugs or failing ignition coils can prevent proper ignition in the cylinders.
- Fuel Delivery Issues: A clogged fuel injector or a failing fuel pump can disrupt the flow of fuel to the engine.
- Vacuum Leaks: Leaks in the intake manifold or vacuum hoses can cause an imbalance in the air-fuel mixture.
- Sensor Failures: Malfunctioning sensors, such as the oxygen sensor or mass airflow sensor, can send incorrect data to the engine control unit (ECU).
What to Do If Your Check Engine Light is Flashing
If your check engine light starts flashing, follow these steps to protect your vehicle and avoid further damage:
- Reduce Speed: Slow down and avoid hard acceleration to minimize stress on the engine.
- Check for Other Symptoms: Pay attention to unusual noises, vibrations, or a loss of power.
- Pull Over Safely: If possible, pull over and turn off the engine to prevent further damage.
- Call a Professional: Contact a trusted auto repair shop, like Kevin's Autos, to diagnose and fix the issue promptly.
Preventing Future Issues
Regular maintenance is key to preventing engine misfires and other issues that can trigger a flashing check engine light. Here are some tips to keep your car running smoothly:
- Replace spark plugs and ignition coils as recommended by your vehicle’s manufacturer.
- Use high-quality fuel and keep your fuel system clean.
- Inspect and replace air filters regularly.
- Schedule routine diagnostics to catch potential problems early.
Conclusion
A flashing check engine light is not something to ignore. It often points to a serious issue, such as an engine misfire, that requires immediate attention. At Kevin's Autos, we’re here to help you diagnose and resolve any problems with your vehicle. Don’t hesitate to reach out to us for expert advice and reliable repairs.
Frequently Asked Questions
Can I drive 20 miles with flashing check engine light?
The rule of thumb is that if the check engine light is flashing, you can't keep driving the car. It's an emergency. Often it indicates an engine misfire. If you keep driving, you will likely cause irreversible damage, mostly to the (expensive) catalytic converter.
How do you know if you have a bad ignition coil or spark plugs?
When a failing ignition coil prevents a spark plug from sparking, the cylinder begins to misfire. This causes the engine to cough, sputter, and shake as it struggles to keep going. The slower you drive, the worse these symptoms of misfiring are likely to become.
How much does it cost to fix a flashing check engine light?
Diagnostic fees alone can range from $50 to $200, while repairs can cost anywhere from a few dollars for a loose gas cap to several thousand dollars for more complex problems. If you find yourself facing a check engine light, it's important not to ignore it.
How do you fix a blinking check engine light?
Locate the negative battery cable, which is usually located under the hood of your vehicle. Disconnect the negative battery cable from the battery terminal. Wait for at least 30 seconds before reconnecting the cable. Once you have reconnected the cable, the check engine light should be reset.
Can I drive my car with the check engine light blinking?
If the engine light is flashing, it's best to stop driving as soon as it's safe to do so. Continuing to drive can cause further damage to the engine or other components, leading to more expensive repairs. In general, you should: Pull Over Safely: Find a safe place to stop as soon as possible.
What does it mean when your check engine light flashes and then goes off?
A flashing check engine light that periodically disappears indicates a potentially serious problem with your car. It may be something minor, but it's an issue that needs investigation fast. Often, this is a wiring problem, but it can also be triggered by a misfire problem or issues with your vehicle's emissions system.
What is the first thing to check when the check engine light comes on?
Check your gas cap first. Many vehicles have a loose gas cap indicator that will be triggered before your check engine light comes on. If your gas cap is loose or the seal is not tight, the vapor leakage can cause your fuel system to trigger the check engine light.
Will bad spark plugs make the check engine light flash?
Yes, spark plugs can cause a blinking check engine light. A blinking or flashing check engine light typically indicates a severe issue, such as an engine misfire. This can occur when spark plugs are worn out, fouled, or not functioning properly, leading to incomplete combustion in one or more cylinders.
Does AutoZone do free scans?
Visit Your Local AutoZone Store for Free Fix Finder Service
You'll receive both a printed and digital copy of the report for your convenience.
Is it better to have a solid or flashing check engine light?
If your check engine light is flashing, you should not be driving. That means there is imminent catastrophic damage about to occur or already occurring if it's a solid check engine light and it's yellow. It means service engine soon. If it's red, it means have it checked if it's flashing, it means stop and shut off.
