What Is a Cold Start in Cars? (All You Need To Know)

Getting to the technical side of your car system, you will know that you still have a lot to learn about its parts. One of the essential pieces of information that you should know is the car engine temperature. 

So, what is a cold start in cars? A cold start happens when you start your car engine during cold temperatures. It is normal to happen, especially during cold weather.

Before using your car, you should first warm up its engine. It is an essential process that every car owner should do. In this process, the oil will lubricate your car engine to keep all moving parts inside to function well when it’s time to run the car. 

Let’s say after parking your car at night when the engine is already turned off, the oil inside it will slowly settle at the bottom of the engine. Though some oil remains at the top of the engine, it is not enough to protect it, especially if you run your engine hard after starting it up.

It is why you are required to give your engine a few seconds to get the oil to circulate again in the engine until it achieves its average temperature. Moreover, During cold temperatures, the viscosity might get thicker, reducing the flow and limiting the engine’s capacity.

Also, it will decrease the layers of protection for your engine. Finally, allowing you to let your engine warm up first during a cold start allows the oil to flow better towards those moving parts slowly. Now let’s see more details about engine starts below.

What Is a Cold Start in Cars

What Does Cold Start Mean In Cars?

A cold start usually happens during cold weather. If your car is at rest for a long time during cold weather, it will have a cold start when you attempt to start it up. 

It is not good to use your car right away. Hence, it would help if you let it warm up first until the temperature of the engine changes. Cold temperature affects the oil inside the engine, so ignoring this state will damage some parts inside your car engine.

What Happens During A Cold Start?

During a cold start, your engine has low temperatures making it more difficult to circulate the oil inside it. As a result, the air that the engine produces is more dense and cool. If this happens, it will directly affect the engine air-fuel ratio, which will also affect the flammability of the mixture.

What Is Temp Considered A Cold Start?

The temperature considered to be a cold start is -20 degrees Celsius. The freezing temperature makes it more challenging for your car engine to face during start-up. 

The internal combustion of your car engine compresses more air on the piston. Due to the rising temperature, the fuel injected into the air will ignite abnormally and burn.

Is A Cold Start Bad?

Yes, a cold start is terrible. However, you can manage to fix it by warming up your car first before using it. 

By this, you are letting the oil get backs to its natural density and start circulating normally throughout your car engine. 

Cold Start Problems

Here are the cold start problems that happen all the time during cold weather.

1. Cold Batteries

Your car engine gets affected during cold weather, especially if you have no garage. The engine is exposed to the temperature leading its parts to get cold like your batteries. If your car batteries are cold, starting your car might be difficult for several attempts. 

2. The Fuel Evaporates Lesser

Suppose you expose it to something cold, the texture and temperature change like any other liquid. If the fuel gets cold, it will not evaporate quickly. The gasoline inside your engine needs to evaporate well to burn.

During cold weather, it will have a lesser evaporating process. As a result, the combustion process does not work as it intends to work. 

3. Thick Engine Oil

Your car engine oil is like syrup in a pancake. When you expose it to a cold temperature, it will thicken. Your engine oil should flow much quicker when not sitting in a cold place. Take note that the type of motor oil you use in your car can stay normal even if it’s cold. 

Cold Start VS. Warm Start 

Between cold and warm start, the warm start is much better. But, of course, if your car has a warm start, the engine oil flows much quicker and supports the parts more successfully. 

Unlike during a cold start, your engine might fail to start-up up several times. As a result, it is time-consuming and might get late to work.


In summary, a cold start in cars is a bad thing. However, you can’t avoid it, especially if it’s winter in your country. The basic process that you should do is give your car engine some time to warm up before using it.

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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