7 Reasons Why Is My Check Engine Light Flashing And Car Shaking

If your check engine light is flashing and your car is shaking, it’s time to take action. This could indicate an underlying issue that you must address before the problem worsens. In this article, Driverevolve will explore 7 possible reasons for “Why is my check engine light flashing and car shaking?” 

By understanding these potential causes, you can better identify what’s wrong with your vehicle and take steps toward resolving the issue quickly and safely.

Check Engine Light Flashing Vs. Steady 

There are 2 kinds of check engine lights, one of which is a steady-on light. The next kind of warning light is the one that flashes nonstop. Check engine lights of the second kind typically indicate a more severe problem.

When this indicator stays on, something is wrong or going to go awry, but the situation isn’t life-threatening. Perhaps it’s just a faulty sensor, which car owners can quickly address during routine maintenance.

So, what does flashing check engine light mean? 

If the warning light continues to blink, there’s likely a much more severe problem. Usually, this indicates that your engine is malfunctioning and unburned gasoline is entering the exhaust. Your catalytic converter’s heat rises as a result, which might lead to irreparable damage.

7 Explanations Why Is My Check Engine Light Flashing And Car Shaking

If your car is shaky and the check engine light is flickering, it almost certainly has an engine problem.

The phrase “misfire” refers to a lack of combustion in one or more of a vehicle’s coils. While it’s usually relatively easy to pinpoint a misfire as the underlying cause of the above problems, tracking out the origin of the misfire is typically much more challenging.

Some of the most typical culprits for an engine misfire are below.

Cylinder Misfires 

When an engine misfires, one or more cylinders don’t produce the power they should. A misfire can be caused by numerous problems, many of which can also lead to a flashing Check Engine Light. For example, you might be dealing with a faulty oxygen sensor or a vacuum leak.

Your vehicle’s acceleration slows down once your engine malfunctions. With the check engine light flashing when accelerating, your automobile may begin to shake. At times, you may even feel like your car abruptly stopped moving.

As your engine idles, it may vibrate more than usual. A misfire is problematic because it often occurs at random moments or when your vehicle is already hot. 

In addition, you’re speeding up the wear and tear on the automobile’s other components. Furthermore, the car’s fuel consumption and emissions will rise throughout this period. 

Defective Spark Plugs

The spark plugs of an internal-combustion vehicle are what really provide the sparks to your cylinders to start the burning process.

Because of wear and tear, spark plugs might be dirty or manifest the wrong gap, making fuel combustion challenging or impossible. This creates a chain reaction you can only reverse by undertaking routine servicing.

One of the best ways to avoid future engine failures is to inspect the spark plugs and replace them if they are worn or have other problems, such as oil in the spark plug wells.

Malfunctioning Coil-Packs/Plug Cables

In automobiles using a coil-on-plug ignition mechanism, electricity gets routed to the cylinders’ spark plugs through a dedicated spark plug cable or coil pack.

The insulating outer covering of these parts can get brittle and break over time and engine-generated high temperatures, causing ignition sparks to leak out ahead of schedule.

Broken Distributor Cover Or Problemed Ignition Coils

Your distributor cover or ignition coils that have failed partially are another possible source of an operational misfire.

Used in many vintage internal combustion vehicles, these devices timed the ignition of your cylinders. Sadly, problems with microcracks and rust have been common in distributor covers, and failures in coils have been widespread due to high temperatures.

Gasoline-Delivery Problems

Defective fuel injectors are another widely-known culprit of vehicle misfires.

Technical or electrical failure of the fuel injectors might result in a cylinder not receiving its full gasoline dose. As a result, there is no fuel for ignition, and the cylinders lose their ability to generate electricity. Usually, the consequence is a noticeable, easily felt shakiness. Thus, once you notice your engine shaking and loss of power, call for professional help.

Pressure Drop

Lack of pressure in one or more pistons can occasionally lead to a misfire scenario. This is especially common in older vehicles or ones with many miles on the motor.

Piston rings, pistons, and valves can all contribute to pressure loss. A blown head gasket can also bring on rapid pressure depletion.

Emissions-Control Issues

The consistent misfire of one or more cylinders may result from malfunctioning or inefficient emissions control systems. This frequently happens when the EGR valve becomes locked in its open position.

An engine can recycle its consumed fuel by bringing the exhaust back into its intake system. Because of this, O2 saturation levels drop below their optimal range, which hinders combustion efficiency.

This kind of misfire typically affects several cylinders at once. This is because, in a multi-cylinder vehicle, the surplus exhaust fumes get recirculated randomly among the chambers. In this case, your oil might even smell like gas.

What To Do If I See A Flashing Check Engine Light 

If you see your “check engine” warning signal come up, it’s time to take your car for a diagnostic examination at the repair shop. Regular service with your specialist is necessary if the “check engine” signal is constantly on.

If your car’s dashboard warning light is flashing, you should visit a repair shop immediately. If you must drive it, do so cautiously and get to the side directly if the car’s performance or pressure sensors keep changing.

Is It Safe To Continue Driving With A Flashing Check Engine Light?

No.

A check engine light flickering and a car trembling excessively are both signs that you should only go as far as required to get to a safe location. This warning light may not be as benign as the “service engine soon” indicator.

Misfiring or a lack of ignition in one or more of a vehicle’s cylinders is the most common cause of these signs, as we’ve discussed previously.

An instance is when too much gasoline is injected into an automobile’s exhaust due to a loss of ignition, causing damage to the car’s catalytic converter. In this case, it’s a must to replace the broken CAT with the best catalytic converter.

Any misfire problem in a car requires prompt attention to determine and solve the underlying problem. This will prevent future issues which are expensive to fix.

If you aren’t confident in identifying and addressing the problem, visit a reliable, independent technician or the service department of your vehicle’s manufacturer.

Wrapping Up 

To protect yourself, it is essential to understand “Why is my check engine light flashing and car shaking?”. The most common causes are problems with the spark plugs, ignition coils, or fuel system components such as the fuel pump or injectors. 

If you have experienced these symptoms in your vehicle, it is best to take it to an auto shop for diagnosis and repair before further damage occurs. Taking care of this issue immediately will save you money on repairs down the road and keep your car running smoothly for years to come! 

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