Check Engine Light Flashing and Car Shaking [Meaning, Causes, & Fix]

The Check Engine Light is a crucial indicator of something wrong with your vehicle. When it starts flashing, it’s an urgent warning that requires immediate attention.

But what does it mean when your car shakes with the flashing Check Engine Light? The answer is that your engine is experiencing some sort of issue, and the shaking is a symptom of the problem.

In this blog post, I’ll delve into the possible reasons why your car might be shaking and the causes of a flashing Check Engine Light.

I’ll also explore what steps you can take to address the problem and keep your vehicle running smoothly.

What Does a Flashing Check Engine Light Mean?

When your car’s check engine light comes on, it indicates a problem with your vehicle’s systems. A flashing check engine light is more serious than a steady one, and it usually means an urgent problem needs to be addressed immediately.

A flashing check engine light could indicate a problem with your car’s engine, transmission, or other systems especially when it’s accompanied by an illuminating traction control light. It’s important to address the issue immediately to avoid further damage and potentially costly repairs.

Common Causes of a Flashing Check Engine Light and Car Shaking

1. Misfiring Spark Plugs

Spark plugs are essential to your car’s engine by igniting the fuel mixture that powers your vehicle. When they aren’t working correctly, your engine can misfire, causing the car to shake. This issue can be caused by worn-out spark plugs or spark plug wires, leading to incomplete combustion and a loss of power.

2. Faulty Oxygen Sensor

Your car’s oxygen sensor helps regulate the engine’s air-fuel mixture, ensuring that it’s running efficiently. A malfunctioning oxygen sensor can cause your engine to run rich or lean, leading to a rough running engine and, in turn, car shaking.

3. Clogged Fuel Filter

The fuel filter removes impurities from your car’s gasoline before it’s sent to the engine. Over time, it can become clogged, leading to a restriction in fuel flow and engine misfires. This issue can cause the car to shake, particularly at idle or under acceleration.

4. Malfunctioning Mass Airflow Sensor

The mass airflow sensor is responsible for measuring the amount of air that’s entering your car’s engine. If it’s not working correctly, your car may not be getting enough air, which can cause it to shake and stall.

5. Vacuum Leak

A vacuum leak occurs when an opening in your car’s intake manifold can cause air to enter the engine where it shouldn’t. This issue can cause the engine to run lean, leading to misfires and shaking.

6. Failing Ignition Coil

The ignition coil is responsible for generating the spark that ignites the fuel in the engine. When it starts to fail, it can cause the engine to misfire and lead to the car shaking. If you notice your car lacks power or the Check Engine Light is flashing, it could be due to a failing ignition coil.

7. Dirty or Clogged Fuel Injectors

Fuel injectors are responsible for spraying fuel into the engine. If they become clogged or dirty, it can cause the engine to run poorly. This issue can lead to rough idling, engine misfires, and car shaking. Regular maintenance and cleaning of the fuel injectors can prevent this issue from occurring.

8. Damaged or Worn Out Engine Mounts

Engine mounts are designed to keep the engine securely in place while absorbing the vibrations caused by the engine’s movement. Over time, the engine mounts can become worn out or damaged, leading to excessive shaking and vibration. If you notice your car shaking more than usual, it could be due to worn-out engine mounts.

9. Faulty Transmission

If the transmission is not functioning correctly, it can cause the car to shake or vibrate. Common causes of transmission issues include low fluid levels, worn-out parts, or a faulty torque converter.

If you notice a significant vibration or shaking that occurs when shifting gears or accelerating, it could be due to transmission problems.

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How To Fix A Flashing Check Engine Light And Shaking Car

1. Check the Gas Cap

A loose or faulty gas cap can cause the Check Engine Light to flash and the car to shake. To fix this, turn off your car and remove the gas cap. Check the seal and make sure it’s not damaged or missing. If it is, replace the gas cap with a new one and tighten it until you hear a clicking sound.

2. Replace the Spark Plugs

Worn or faulty spark plugs can cause the engine to misfire, leading to a flashing Check Engine Light and car shaking. To fix this, locate the spark plugs in your car’s engine and remove them with a spark plug socket.

Check the condition of each spark plug and replace any worn or damaged ones with new ones. Finally, reinsert the new spark plugs and tighten them with the spark plug socket.

3. Replace the Ignition Coils

Faulty ignition coils can also cause the engine to misfire, resulting in a flashing Check Engine Light and car shaking. To fix this, locate the ignition coils in your car’s engine and remove them. Check each coil’s condition and replace any worn or damaged ones with new ones. Finally, reinsert the new ignition coils and tighten them.

4. Replace the Oxygen Sensor

A malfunctioning oxygen sensor can cause the Check Engine Light to flash and the car to shake. This component is responsible for monitoring the oxygen levels in the exhaust and adjusting the fuel-to-air ratio accordingly.

To fix this, locate the oxygen sensor in your car’s exhaust system and remove it. Replace it with a new sensor and tighten it until it’s snug.

5. Clean or Replace the Mass Airflow Sensor

A dirty or faulty mass airflow sensor can cause the engine to run poorly, resulting in a flashing Check Engine Light and car shaking. To fix this, locate the mass airflow sensor in your car’s engine and remove it.

Clean it with a mass airflow sensor cleaner, or replace it with a new one. Finally, reinsert the cleaned or new mass airflow sensor and tighten it.

Tips to Prevent the Flashing Check Engine Light 

1. Regular Maintenance

Regular maintenance is essential to keep your car in good condition and prevent potential problems that may trigger the Check Engine Light. Follow your car’s maintenance schedule and have it checked regularly by a certified mechanic.

2. Fuel Quality

Poor quality fuel can lead to a buildup of deposits in your engine, which can trigger the Check Engine Light. Always fill up at reputable gas stations that sell high-quality fuel.

3. Air Filter

A dirty air filter can reduce airflow to the engine and cause it to run poorly, leading to the Check Engine Light flashing. Check and replace the air filter as recommended by your car’s manufacturer.

4. Oil Changes

Regular oil changes are essential to keep your engine running smoothly. Neglecting to change the oil can cause a buildup of sludge, leading to engine problems and triggering the Check Engine Light.

5. Driving Habits

Avoid aggressive driving, such as rapid acceleration and hard braking, which can stress your engine and cause it to malfunction. Also, avoid overloading your car with excess weight, as this can cause the suspension and drivetrain to work harder than they should.

6. Electrical Components

Regularly check your car’s electrical components, such as the battery and alternator, to ensure they are working correctly. Faulty electrical components can cause the Check Engine Light to flash and affect your car’s performance.

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Conclusion

When you see the Check Engine Light flashing on your dashboard and your car shaking, it can be a nerve-wracking experience.

First and foremost, identify the common causes of a flashing Check Engine Light and car shaking. These include issues with the spark plugs, ignition coils, fuel injectors, and oxygen sensors. However, understanding these common causes will help to narrow down the problem and focus on the appropriate solution.