Car Shakes on Cold Start (Why and What to Do? Explained!)

Cars aren’t always in perfect condition. You will encounter problems every now and then. But, there’s a way to prevent further problems too. All you have to do is to always check your car and make sure to keep up with your maintenance. Especially, when it comes to your car engine.

So, what can be the reason why your car shakes on cold start? Is it because of cold engine? An unfastened heat shield or heat-sensitive component is frequently the source of startup noise and vibration. Some common culprits include the cold air box and ducting of intake systems, as well as exhaust pipes, connections and manifolds. Vibrations cause metal parts to expand into their new positions.

During idling, the engine vibrates after it has sat overnight (with a cold engine). Automobile engines, in general, dislike and perform poorly in cold weather. In the morning, when you turn the ignition switch to on, the coolant temperature sensor immediately reads the temperature and transmits this information to the computer.

So, in this page, we are sharing more facts about why your car shakes or vibrates on cold start and what you have to do when it occurs.

So, without further ado, let us begin!

Car Shakes on Cold Start

Why Does My Car Shake on Cold Start?

Here are several reasons why your car shakes or vibrates during cold start. 

1. Your Tank’s Fuel is Low.

No matter how obvious it may seem, you should always check the fuel level in your tank for the simple reason that it could be low. This may be the cause of shaking when you cold start your car.

2. You’re Using a Low-Quality Fuel.

Low-quality fuel is available at many gas stations, which can also contain a significant amount of water. If you want to be sure your fuel is water-free, fill a bottle halfway with water and leave it for a few hours. In the event that there is water present, it will sink to the bottom where it will be readily apparent.

If your diesel car’s engine stalls when you try to start it in the cold, it’s possible that the frozen fuel is to blame. The freezing point of diesel is well-known, and it can be dangerous in extremely cold weather.

3. Your Car Battery Isn’t Charged.

Charging is required for a wide range of devices and equipment in each vehicle. Although the motor and all energy consumers are off, some devices may still use a small amount of power even when they are not in use.

An ignition relay or fuel pump, for example, may not function properly because of a partially discharged battery. If starting the internal combustion engine has become more difficult, you should also check the starter.

4. You Pumped Your Fuel Bad.

The fuel pump is the most common cause of a vehicle’s engine starting and then stumbling to a halt. Incorrect engine operation can be caused by its malfunction, failure, or clogging of the fuel filter. A clogged fuel filter will either not pass the fuel through itself at all or pass it, but at a very slow rate.

If this is the case, fuel will enter the cylinders, but there will be insufficient fuel to ensure optimal engine performance after the engine is started. As a result, the vehicle will shake and possibly stall a few seconds after starting. Ask yourself how long it has been since you had the fuel filter changed. This component must be replaced on a regular basis.

5. You Have Bad Spark Plugs.

The ignition system relies heavily on the performance of the spark plugs. Spark plugs, like all other auto parts, degrade over time and eventually stop working altogether.

Aside from wear, another possible cause is the formation of carbon deposits, which can be either black or white, due to a variety of reasons. When the air-fuel mixture is formed incorrectly or the fuel is of poor quality, carbon deposits are common.

6. You Have Faulty Spark Plug Wires.

It’s possible that the insulation on the high-voltage wires that connect the spark plugs to the ignition distributor or coil will wear out over time. Humidity can cause a voltage short circuit in the insulation, which can lead to abnormal engine vibrations and, ultimately, to poor engine performance.

7. You Have A Worn-out Timing Belt or Timing Chain.

Because the chain or belt can no longer be properly adjusted after prolonged use, it will eventually wear out. When the engine is started in severe frost, this problem may occur even if the belt or chain is worn out.

8. You Have A Bad Oxygen Sensor.

Poor compression in the engine’s cylinders is one of the most annoying issues. It’s possible that the internal combustion engine is nearing the end of its service life and will soon require a major overhaul.

9. The Faulty Engine Mounts.

The most common cause of shaky driving is faulty engine mounts. When the car is idling, the problem can be felt more clearly.

When the temperature in the engine compartment has not yet risen, the cold engine vibrates the most. After a period of time, the rubber in the support structure will soften, reducing the amount of vibration. The engine mounts must be examined in order to make an accurate determination.

10. Your Car Has Bad Injectors

When starting a diesel engine with dirty or failing injectors, the cold engine will vibrate.

11. You Car Has Faulty Idle Speed Sensor

RPM can float on a cold engine due to issues with idle speed or actuators. The crankshaft speed can fall to dangerously low levels during sudden acceleration, causing the engine to almost stall. Strong vibrations will be felt as a result of this.

Is it normal when the car shakes on cold start?

It’s not normal for a “good condition car” to shake during cold start. If this happened to your car, there are probably problems that you have to check and get fixed as soon as possible.

Starting a car can cause vibrations, and this is a common problem. Engine and fuel problems are the most common causes of the car shaking when it is turned on, but there are a few other possibilities.

When starting a cold engine, vibration is a common occurrence. Vibrations may not be felt for the first few starts after the motor has been warmed up. These symptoms are often a sign of underlying issues that need to be addressed.

Vibrations might be constant or apparent in a certain working mode, depending on whether the machine is heated or loaded (idle or high speed, cold or hot). When an internal combustion engine is cold, vibrations can be felt, but when the engine warms up, the vibrations go away completely.

What to do when your car shakes on cold start?

There are so many reasons why your car shakes when cold starting. So, it’s best to have a full diagnostic done of all the listed parts to find out what the problem is. Start by inspecting the engine mounts, which are often the source of vibrations in a vehicle.


In summary, there are lots of reasons why your car shakes on a cold start. This may be because of your poor quality fuel, faulty spark plugs, faulty spark plug wires, discharged car battery, faulty engine mounts or oxygen sensor, and many more. 

On the brighter side, there’s a way to fix it. You just have to inspect the mentioned parts to know the problems with your car.

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Image credits – Canva

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My name is Hank, and I've been in the automotive industry for 27 years. I've been working in my own auto repair shop for the last 13 years, and now I want to help you here, on my blog. Let me know if you have any questions. Read more