Blinking Check Engine Light (Causes and Fixes)

Geoff Cudd

The blinking check engine light is a warning signal on the dashboard of a vehicle's instrument panel. It is a diagnostic tool built into modern cars to notify the driver of potential issues with the engine, emissions, or other essential systems.

The check engine light is a part of the onboard diagnostic system (OBD) that monitors the engine's performance and emissions.

Ignoring a blinking check engine light can lead to more severe damage to the vehicle and compromise its safety and performance.

It is essential to understand the importance of the blinking check engine light and get inspected and repaired promptly to prevent any further complications.

Understanding the Onboard Diagnostic System (OBD)

The Onboard Diagnostic System, commonly called OBD, is an electronic system installed in most modern cars to monitor the vehicle's performance and report potential issues.

The OBD system tracks everything from the engine's fuel efficiency to the car's exhaust emissions.

The OBD system alerts the driver of any car performance issues. The onboard system activates an illuminated "check engine" light on the dashboard if it detecs issue requiring attention.

It also stores a code that a diagnostic tool can read to identify the specific problem.

The vehicle's OBD system employs a range of sensors to constantly check the operation of the engine, transmission, and emissions control systems.

These sensors collect vital data including the auto's speed, temperature, and fuel usage. This allows for effective monitoring and control of the car's functioning.

The Onboard Diagnostics (OBD) system recognizes various issues associated with a car, including complications related to its fuel system, exhaust control system, and spark system.

It spots problems in the vehicle's transmission and other components, affecting its performance.

The OBD system renders crucial aid to mechanics when it comes to detecting and repairing issues with a car. When a mechanic connects a diagnostic tool to the vehicle's OBD system, it reads the stored code and provides information on the specific issue. This makes it easier and faster for mechanics to identify and resolve problems with the vehicle.

What Causes the Check Engine Light to Blink?

The check engine light is essential to a vehicle's onboard diagnostic system. When the light illuminates, it signals that the car's computer detects an issue.

In some cases, the check engine light may blink. Blinking indicates a more severe problem that requires immediate attention. Most commonly these issues may be with the vehicle’s engine, and are therefore more dangerous.

Some of the most common causes of a blinking check engine light include:

Misfired motor

One common cause of a blinking check engine light is a misfiring engine. This occurs when the engine fails to ignite properly, resulting in a loss of power and a rough-running engine.

Problem with the automobile's catalytic converter

The function of a catalytic converter is to decrease vehicle exhaust. However, if it malfunctions, it can impact the motor's performance and fuel efficiency detrimentally.

A malfunctioning catalytic converter also triggers the check engine light to blink.

Malfunctioning sensor

Another common cause of a blinking check engine light is a malfunctioning sensor. The vehicle's onboard diagnostic system relies on various sensors to monitor the engine's performance and detect issues. If one of these sensors malfunctions, the check engine light can blink.

Dangers of Ignoring a Blinking Check Engine Light

While a steady check engine light may indicate a minor issue, a blinking light is an urgent signal that something is wrong. Ignoring a blinking check engine light can significantly impact a vehicle's performance, safety, and longevity.

One of the primary dangers of ignoring a blinking check engine light is the potential for further damage to the vehicle. A blinking light often indicates a significant issue with the vehicle's engine or emissions system. Continuing to drive the car may exacerbate the problem, leading to further damage. This can result in costly repairs and permanent reliability loss.

Another danger of ignoring a blinking check engine light is the potential impact on safety. A blinking light can indicate a problem with the vehicle's ignition system, which can cause the engine to misfire or stall. If that’s the case, it can lead to a loss of power or control while driving, potentially leading to accidents or other safety hazards.

Ignoring a blinking check engine light can also negatively impact a vehicle's fuel efficiency and emissions. The car may need to work harder to compensate for the issue.

Finally, ignoring a blinking check engine light can increase repair costs. A minor issue that triggers a steady check engine light can quickly become a larger and more expensive problem. The longer a problem is ignored, the more it can impact other vehicle components.

What to Do When You Notice a Blinking Check Engine Light

When this light blinks, respond promptly and take appropriate action to prevent further damage, safety hazards, and repair costs.

Here are some steps to take when your check engine light starts blinking.

Step 1: Pull over

Driving the vehicle with a blinking check engine light can increase the issue. Find a safe place to pull over, turn off the engine, and wait for the vehicle to cool down.

Step 2: Check the vehicle’s owner's manual

The next step is to check the vehicle's owner's manual for guidance. The manual may contain information on the blinking check engine light and instructions for the next steps.

If you need clarification, tow the automobile to an authorized technician for an accurate evaluation.

Step 3: Examine the vehicle

Ensure that the vehicle's liquids, such as oil, coolant, and transmission fluid, are all at suitable levels.

You can also check the gas cap to ensure it is tight. A loose or faulty gas cap can trigger the check engine light to blink.

Step 4: Fix it immediately

Swiftly take action to rectify the situation, whether you detect it by yourself or have an experienced mechanic diagnose it.

Continuing to drive the vehicle can lead to greater damage and safety concerns.

How To Diagnose and Repair Check Engine Light Issues

Here is an overview of how to diagnose and fix check engine light issues.

First, use a diagnostic tool to read the vehicle's onboard computer. This tool retrieves error codes stored in the vehicle's computer, providing valuable information about the issue. Mechanics use this information to identify the root cause of the problem.

Once you have identified the root cause of the issue, perform a series of tests to confirm the diagnosis. For example, you may use a multimeter to test the electrical circuits, a vacuum gauge to test the vacuum system, or a compression gauge to test the engine's compression.

Once the diagnosis is confirmed, develop a repair plan. This may involve replacing a faulty component, repairing a damaged system, or performing routine maintenance.

Ensure the issue does not recur during the repair process. For example, replace a faulty component with a higher-quality part or adjust the vehicle's systems to prevent further problems.

Once the repair is complete, use the diagnostic tool to clear the error codes from the vehicle's computer. Perform a final test to ensure the issue is resolved.

How to Avoid Check Engine Light Issues

Maintaining your vehicle ensures it runs smoothly and prevents check engine light issues.

Keep your car in good condition by following the manufacturer's recommended maintenance schedule.

Regular oil changes, tire rotations, and fluid checks help keep your vehicle running efficiently.

Keeping an eye on your vehicle's dashboard warning lights is also important. Rectify the problem quickly if a warning light shows up.  Ignoring warning lights can lead to more severe issues down the road.

Regularly checking your vehicle's air filter also helps prevent engine performance issues that may trigger the check engine light.

Ensure your gas cap is tight as well. A loose or faulty gas cap can cause the check engine light to come on. It is an easy fix that can save you from unnecessary repairs.

Take care of your vehicle's battery. Corroded battery terminals or a weak battery can cause electrical issues that may trigger the check engine light.

Use high-quality fuel and engine oil prevent engine performance issues that can cause the check engine light to come on. Check your vehicle's emission system regularly to prevent malfunctioning.

Finally, take your vehicle to a qualified mechanic for regular inspections. A qualified mechanic can identify potential issues before they become major problems. They will help you keep your car in good working order.

These tips will help prevent check engine light issues and ensure your vehicle runs smoothly.