Why Does The Car Shake When Starting?

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When you turn the key, and your car starts to shake? Suddenly, that routine task becomes a source of anxiety and concern. When starting, car shaking can be caused by various issues, from simple problems with your wheels to more complex issues with your engine or transmission. In this comprehensive blog post, we’ll take a deep dive into the possible causes of car shaking when starting and what you can do to fix the problem.


8 Reasons Why Your Car Shake When Starting

If your car shakes when you start it, that’s a clear sign of certain issues that you need to deal with. While the issue is quite common for a lot of car owners, and most probably everyone has experienced this at one point or another, you should still consider knowing why it occurs.

Here are eight possible reasons that can cause this issue:

1. Faulty/Worn Out Plugs

One of the most common causes of a shaky engine is worn out or faulty plugs. These deteriorated parts can cause the car to shake and vibrate and can transform into a more potential issue really fast as they prevent the fuel-air mixture from igniting adequately in the cylinders.

This may cause misfiring during idling and even at high speeds. As a result, your car starts to vibrate when you start it or drive it at high speeds.

How To Fix: The easiest and no-brainer way to solve this issue is to install a new set of spark plugs so you can stop the vibration. In some cases, you may get away easy on your pocket by getting dirty spark plugs cleaned and repurposed, but we won’t suggest you do so.

It’s always better to replace them after a certain time as they’re quite inexpensive and essential for your car’s driving efficiency.

2. Disconnected/Loose Hoses

Sometimes, when your car’s hose is either disconnected or loose, it may cause the car to vibrate and shake and should be dealt with as quickly as possible. Hoses are responsible for carrying the radiator coolant, vacuum, and air-fuel mixture, and when they’re loose, your engine starts malfunctioning.

How To Fix: If the hoses are found to be loose, then just reattach them tightly. However, if they’re damaged, replace them with new ones instead to get rid of the issue.

3. Damaged Motor Mounts

The motor mounts are responsible for controlling the road shocks and vibrations, which makes it quite evident why it can be a possible reason for the vibrations happening in your car right now. It also absorbs the road shocks to support the engine in its compartment.

How To Fix: You may consider replacing the faulty motor mounts with the help of a professional mechanic.

4. Issues With the Brakes

Brake issues are very likely to cause vibrations in your car, especially when you’re dealing with warped brake rotors. They’re silver-coloured round-shaped components located in the disc brake system installed in your car.

Due to regular wear and tear, they can deteriorate and become inappropriate to be used in your car. They dismount from their original shape and can cause immense vibrations in your car because they’re compressed with brake pads and callipers.

How To Fix: You can easily prevent this issue by getting your rotors and brakes checked timely and getting any necessary repairs or replacements done.

5. Imbalanced Set of Wheels

Mostly when people deal with their vehicle vibrating, they may suspect an issue with the engine and will most probably overlook the tires of their vehicle. Imbalanced tires can cause several issues with the car, out of which the most common one is vibrations.

Sometimes, it can also occur due to some particles being stuck on your wheels, which can be get ridden off by cleaning.

How To Fix: Make sure that you’re using the right set of wheels compatible with your car. You can look at the sidewall of your stock tires to know a perfect size. Also, make sure to get your wheels cleaned and get rid of unnecessary dirt.

6. Engine Plight

Out of all other reasons, this one is the most probable cause of your car shaking when turning it on. Engine issues are often linked to vibrations in your car, which may occur due to various reasons, such as the engine not getting enough spark, fuel, or air to run properly.

How To Fix: When encountering this issue, you may consider replacing your old spark plugs with new ones or changing any dirty air filters in your car.

7. Inadequate Fuel Intake Adjustments

The fuel intake system of your car also needs to be in sync to prevent vibrations in your car. Any slight variations in the adjustment of your car’s fuel intake system can cause the engine to provoke vibrations in the car while turning it on.

This mostly occurs because an improper adjustment prevents the engine from getting the required fuel-air mixture to perform optimally.

How To Fix: To fix this issue, you need to adjust the idle speed on your vehicle’s carburettor and consider getting the fuel intake system cleaned thoroughly.

8. Incompatible Timing Belt

The timing belt is responsible for providing insights into the functioning of several minor and critical components of the engine of your vehicle. That being said, any potential issues with the timing belt can also lead to the malfunctioning of certain belt-driven components in your vehicle, such as fans.

Therefore, several of these small components malfunctions causing your car to vibrate.

How To Fix: Consider checking the cable belts for any signs of damage or loose ends and if you find any worn-out ones, make sure to get them replaced right away to get rid of the problem.


How To Get Rid of The Problem Once and for All?

Car shaking when starting can be a very frustrating issue to deal with, especially when you have no idea about what’s going on with your vehicle. Fortunately, solving the issue isn’t that worrisome and just requires you to follow the steps given below:

Identify the Root Cause

Foremost, you should try identifying the root cause of the problem to fix it permanently. It’s a good idea to start inspecting the engine as it is the most common source of vibrations in your car, but there can be several other reasons behind it, regardless.

A simple way to identify the problem is by looking at the diagnostic trouble codes. You can use an OBDII scanner to determine if your cylinder has any misfires. This will allow you to find the source of the issue quickly and easily.

Find The Issue

Now that you have identified the root cause of the issue, it’s now time to analyze the problem to work on an effective solution. Depending on the type of misfire that occurred in your engine; there can be several ways to tackle the issue, as given below:

Single-Cylinder Misfires

These generally occur as a result of problems in the fuel injector or ignition. In such events, you should check the ignition coils, spark plugs, and plug wires. In some cases, it may also occur due to the cylinder’s coil, which is quite easy to determine.

Random Misfires

Many problems affecting the overall integrity of your car’s engine are caused by the engine support system comprising the fuel supply, air intake, and electronic systems. It’s recommended to check for sensor failures, leaking air, and clogged airflow sensors.

Mechanical Failures

Mechanical problems refer to any issues with the piston rings, head gasket, or camshaft. They can cause cylinder misfires and cause your car to shake. It may also be possible that an unbalanced rotating assembly may cause the car to shake without any misfires at all.

Replace The Faulty Parts

Once you’ve identified the problem, it’s time to get the damaged parts replaced with new ones and stop the shaking once and for all. It’s always recommended to get the necessary repairs done by a professional unless you know what you’re doing.


Car Shaking When Starting While Check Engine Light is on – What Does It Mean?

If your car is shaking and the check engine light is also turned on, it’s a clear sign that there’s a problem with your engine. There can be more than one problematic component which is causing the check engine light to turn on.

In case the light is blinking, it may indicate an engine misfire or point towards common causes like a faulty ignition coil, bad spark plugs, or a failing engine sensor. At this point, it is recommended to prevent driving your vehicle any further.


What If the Issue Occurs Mostly in The Morning?

If the issue occurs mostly in the morning, then it may link to issues such as cold engines that lead to higher RPMs. When your car’s engine is cold, the temperature of the coolant or oil may drop and result in higher friction.

This, in turn, makes it hard for your engine to produce a similar amount of power as in warm temperatures and causes vibration and shaking. 


Final Words

Car shaking when starting can be caused by a variety of issues, as stated above. Understanding the underlying causes and taking steps to address the problem is crucial to maintaining the health and longevity of your vehicle. By following the tips and advice outlined in this blog post, you can ensure that your car runs smoothly and avoid costly repairs down the road.


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