Skip to Content

How Long Can I Keep My Engine Running? (Answered)

The engine is considered a vital part of a car. An engine can be damaged due to lack of maintenance and proper use and reduce the efficiency of the vehicle. In today’s article, we will discuss the functionality of a car engine. 

How long can I keep my engine running?

Although you can keep the car engine running for as long as you want, it should never run for more than 30 seconds to 1 minute. This prevents damage to the engine and ensures the fuel efficiency of the vehicle. So, it is better not to keep the engine running to increase the life of the engine. 

The engine can be compared to the heart of your car. The main functionality of a car engine is to keep it running. But in some cases, when you are driving, you may need to stop for a while. 

You may have to refuel, buy fast food, or stop for a short time. In this case, you may want to keep the engine running to get your work done. But this will cause great damage to the engine of your car without you knowing. 

When the engine is turned on without stopping the car, fuel is wasted and the efficiency of the engine is reduced. And that is why experts recommend keeping the engine running for less than one minute to prevent shortening the lifespan of your car engine. 

Below is a brief discussion on how long can you keep your engine running in different situations:  

While parked: 

If you keep the engine running for more than 5 minutes in a parked condition, you will notice that the engine temperature of the car is rising more than normal. 

However, in colder climates, the engine can be kept parked for longer than this. However, a higher-than-normal engine temperature is a bad sign for the car. 

After a jump start: 

It is better to keep the car engine running after the car jump starts. But the car should not be idle after starting the engine. 

It is recommended to keep your car running at least 30 minutes after a jump start so that the battery can be fully charged. But instead of standing idle, you should drive the car. 

To charge the battery: 

It is recommended to keep your car engine running e 30 minutes to charge the battery fully. This will prevent the battery from losing its power again. During this time, you need to keep your car running instead of standing.

Is it bad to keep the engine running? Can you keep a car running forever? 

You should not keep the engine running because it will consume more fuel and is the efficiency of the engine. As a result, you will need to change the engine oil very frequently. 

Apart from that, keeping the engine running affects the environment as well by causing air pollution due to carbon emissions. When you keep the engine running for a long time, it may damage the engine components as well. 

It is possible to keep a car running forever with an infinite amount of fuel. But considering the reality, keeping an engine running for a long time can cause some serious issues

It may reduce the lifespan of your engine. That is why you can idle your vehicle for a few minutes when driving for a long time or before turning off the engine. This will balance the efficiency of the engine.

How long is too long to keep your car running? Is it illegal to sit with the engine running? 

You can simply keep your car engine idle for at least 30 seconds to one minute. If you keep running the engine longer than that, it will cause air pollution. 

In some cases, such as a jump start or to charge the battery, you need to keep the engine running idle for more than 20 minutes. Generally, keeping your engine running idle for longer than 30 minutes can be considered too long. 

It is considered illegal to sit with the engine running. This comes under Section 42 of the Road Traffic Act 1988 which states that you must not leave a vehicle engine running unnecessarily while the engine is stationary on a public road. 

This act will enforce Rule 123 of the Highway Code. But keeping the engine running while parked will not come under this law.

What happens if you keep your engine running?  

Although most drivers keep the engine running without noticing the faults that result from idling the car’s engine, it can affect the engine’s lifespan and fuel efficiency in the future. 

The engine consists of some sensitive components that can be harmed if the engine is kept running idle for a long time. It can be the engine to heat up quickly and consume coolant. 

If you keep your engine running, it will use more oil and consume fuel. As a result, you will need to change the engine oil frequently and fuel efficiency will be lowered. Below is a brief discussion on what happens if you keep the engine running: 

Causes carbon emission and air pollution: 

When you keep the engine running idle for a long time, it starts to emit dangerous carbon dioxide gas harmful to the environment. As a result, this causes air pollution. 

Carbon emission is responsible for the increasing temperature throughout the world. That is why to reduce carbon emission you need to avoid running the engine while idle.

Increases the engine temperature: 

When you keep the engine running for a long time, it increases the temperature of the engine.

As a result, the burning of engine oil increases. Increasing engine temperature could lead to serious engine component issues. That is why it is always recommended to avoid keeping the engine running for a long time.

Decreases the lifespan of engine and fuel efficiency:

As mentioned earlier, when you keep the engine running for a long time, it will increase the engine temperature and decrease the engine. This will also decrease the lifespan of the engine. 

When you keep the engine running for a long time, it will consume more fuel than normal.

Can I leave my engine running for an hour? Can I leave my car running all day? 

Leaving the engine running for an hour can be harmful to the performance of the engine. Although it will not affect the car at the beginning, eventually the engine will start to drop its performance. 

In addition to that, if you leave your car engine running and idling for more than one hour, it will waste almost one gallon of gas and a good amount of engine oil. 

Generally, leaving your car running all day will not harm it. But you need to have a properly functioning engine cooling system to keep this car running all day without having any malfunction in the engine. 

It is recommended that you take a break while driving or keep your engine on for a long time. This will eventually balance the performance of your engine and provide you with a higher fuel efficiency after a long time.

How to keep your engine running longer?  

If you keep your engine running for a long time, it will start to deteriorate its performance. Apart from that, keeping the engine running and idle for a long time can cause lower fuel efficiency and engine heating issues. 

This also adds environmental pollution and unnecessary carbon emission from your car. That is why you need to make sure you do not keep your engine running unnecessarily. 

This will extend the lifespan of your engine as well as provide you with a higher fuel economy and efficiency. Below is a brief discussion on some tips regarding how you can keep your engine running longer: 

Maintain the battery: 

The first thing you’ll need to do to maintain your engine and keep it running longer is to maintain the battery. 

A battery can produce the power that is passed to the engine so that the car can move. In addition to that, without maintaining the battery, your engine won’t be able to provide you with the best performance.

Change the oil and filters regularly: 

You need to change the engine oil and the filters regularly. The dirty engine oil reduces the efficiency of the engine as well as its lifespan. Moreover, dirty oil filters will also decrease the fuel economy of the engine. 

Drive smoothly: 

The most important part to keep your engine running properly is to drive the car smoothly. It means you need to balance the behavior of the engine without putting pressure on it. 

Final thoughts 

You can keep your car engine running for a long time, but keeping it idle for more than one minute might cause damage to the engine components. It also causes air pollution, increases coolant consumption, and reduces engine efficiency. So, you should not keep your engine running idle for too long.