Why is the check engine light flashing and my car shaking?
The check engine light is meant to get your attention, even if it just stays illuminated on your dashboard. How much more anxiety-provoking is it when the light flashes? And even worse, what does it mean when the check engine light flashes and your car shakes?
This guide will answer those questions. Not only will you learn the most common causes of this serious condition, but we’ll also help you find a solution to it. We’ve also included some frequently asked questions at the end of the article.
Why is the check engine light flashing and my car shaking
When the check engine light starts flashing, you know something serious is going on. If your car starts shaking, you’ll be even more worried. Perhaps you have a faulty ignition coil, a faulty spark plug, a faulty fuel injector, a faulty engine sensor, or a misfire caused by low compression. Let’s take a closer look at these causes.
1. Your engine is experiencing a misfire in one cylinder
When a misfire occurs, the combustion reaction does not proceed normally. In this situation, one cylinder does not ignite. Misfires can occur during engine start-up, when the vehicle is idling, or when accelerating. It feels choppy and the check engine light always comes on.
But a misfire isn’t actually the problem that needs to be fixed. There are things that cause a misfire, which I’ll explain in the next example. Any of the remaining issues can cause the engine to misfire.
2. Faulty Ignition Coil
Ignition coils or ignition coil packs are often the cause of misfires and vibrations. Ignition coils act as small transformers that generate high voltage currents that power the spark plugs.
If your ignition coil is faulty, not only will your engine misfire, it will also idle rough and you will notice a loss of power. Additionally, your engine will work harder, resulting in poor fuel economy and may be difficult to start.
3. Bad Spark Plugs
Spark plugs are also a common culprit, especially if they haven’t been changed for a long time. When spark plugs stop working, they can cause misfires in the cylinders. The engine will jerk and shudder, and the check engine light will come on.
Over time, spark plugs naturally become fouled. They become dirty and worn out, and are no longer able to produce the spark needed to ignite the fuel-air mixture. For this reason, it is best to replace your spark plugs at the recommended service intervals to avoid problems.
4. Faulty fuel injectors
Fuel is needed in the combustion chamber to ensure smooth operation. Lack of fuel can make the engine hard to start and cause misfires. Faulty fuel injectors can cause such problems. Direct injection systems ensure that fuel reaches every cylinder. The amount of fuel injected must be precise and is controlled by the Electronic Control Unit (ECU). The injectors also need to produce an even spray pattern to ensure efficient combustion.
Injectors fail when they leak or become clogged. The tips can become dirty and cause blockages. Additionally, leftover fuel will cause hydrocarbon deposits on the ends. If that’s not the problem, it could also be that seals have worn down and fuel is getting into the system.
5. Engine Sensor Failure
Today’s car engines are equipped with a variety of sensors that ensure everything runs smoothly. These sensors are responsible for monitoring the operation of the engine and making adjustments. Some sensors measure airflow, while others monitor fuel pressure and engine controls.
If one of the sensors fails, your engine will experience poor performance. Depending on the severity of the problem, you may experience misfires and the check engine light may start flashing.
6. Low Compression
Low compression in an engine means that the cylinders can’t compress the right amount of air. Without the proper air density to mix with the fuel, your engine’s performance and efficiency will decrease.
You will notice misfires and poor fuel consumption. Your engine may also be difficult to start. Low compression can cause several problems, including: B. Piston holes, cylinder head defects, or leaking valves. Low compression is one of the most difficult problems to diagnose and fix.
How to Fix a Flashing Check Engine Light and Car Shaking
To fix a flashing check engine light like a pro, you need to start thinking like us. Our team deals with these issues every day, so we’re very familiar with repairs. First, read the service manual to get advice tailored to your vehicle.
Then, follow the steps.
1) Reading Error Codes
The computer sets codes that indicate what’s going on when the Check Engine Light comes on. You can hook up a compatible code scanner to read these codes. It could be a common error like P0300, but it’s not very helpful if there aren’t other codes to pair it with.
We have a full error code library to help you figure out what’s going on. Being able to identify the problem with just the code can save you a lot of time on repairs.
2) Check the ignition coils and spark plugs
It’s possible that the error code points to a specific cylinder. If so, that’s good news. At least you know where the misfire is occurring. The next step is to check the spark plugs and ignition coils for that cylinder. Depending on your vehicle model, you may need to remove other parts. Some vehicles require you to remove the intake manifold or engine cover before you can access these components. It’s also important to know the order of the engine’s cylinders so you know which engine you’re looking at.
You can try replacing the spark plugs or ignition coils to see if that fixes the problem. Be careful when removing these parts, especially the spark plugs, as they can be difficult to remove. You don’t want your spark plugs to break off in the cylinder head.
Even if your spark plugs don’t appear worn, there could be a gap problem. Measure your spark plug gap and adjust if necessary. Check the clearance specifications in your service manual to get the correct measurement for your vehicle.
3) Check the injectors
There are several ways to check your fuel injectors. Let’s look at some of the most common options.
Click Test
– Start the engine
– Let it idle for a few minutes
– With the engine running, press the end of a metal screwdriver against the fuel injector.
– Hold the other end of the screwdriver against your ear, but be careful not to bring any objects near the running motor.
– If you hear a clicking sound, the injector is working properly.
– If you don’t hear anything, the injector will need to be replaced or cleaned.
– Repeat the test for all injectors.
Voltage Test
– Check your service manual for the correct electrical resistance or ohm value for your injectors.
– Perform this test when the injectors are cold.
– Turn on the ignition, but do not start the engine.
– Connect a test light or voltmeter to the negative battery terminal.
– Disconnect the electrical connector from the injector.
– Connect the injector wire connections to a voltmeter to see if you get the correct reading.
– Repeat for each injector
Leak test
– Locate the injectors
– Smell carefully around the injectors for signs of gasoline.
– Inspect the injectors for signs of leaking or dripping.
– Perform this test for all injectors.
– Some people prefer to do multiple tests to make sure their results are accurate.
4) Contact a professional
If you’ve gone through all the steps and still can’t figure out what’s going on, go to a repair shop. To identify the problem, contact your local mechanic.
Whether you fix the problem yourself or have a professional check it out, do not drive your car if your check engine light is flashing. Fix the problem before continuing to drive to avoid permanent damage to your engine.
Can I drive my car if my check engine light is flashing?
No, if your check engine light is flashing you need to pull over in a safe place and fix the problem. Continuing to drive your car can cause further damage and additional repair costs. If your check engine light is on, you may be able to drive your car home first.
Will an engine misfire fix itself?
No, a misfire is caused by a mechanical defect. When your engine misfires, it means that one of the cylinders is failing. This problem can be caused by bad spark plugs, low compression, faulty ignition coils, faulty injectors, or faulty sensors.
How long can you drive with your check engine light flashing?
You should never drive if your check engine light is flashing. This warning light is letting you know something is seriously wrong and should never be ignored. Instead, find a safe place where you can pull over and turn off the engine. We know how frustrating car troubles can be, especially those related to a flashing check engine light. This is a serious issue that even we don’t take lightly.
It’s important to fix the problem right away so your car can run smoothly. If you’re stuck, read our guide to get your car running again without flashing dashboard lights.