How to drive a car with manual transmission to save fuel? Questions about neutral coasting

The characteristics of the EFI engine is automatic fuel replenishment, which will not be reflected in the speed, because the oil replenishment is to ensure the operation of the engine, there is no impact on the speed, the neutral gear will be replenished according to the fuel consumption of the idle speed, and the higher speed will naturally be higher than when the gear is attached, the average person does not understand the structural performance of the car, they will only look at the instrument, but many conditions can not be seen on the instrument, so it will make many people who are not good enough to think that the EFI car is fuel-saving in neutral sliding, in fact, the technician who originally heard 4S said that the principle of EFI neutral fuel consumption is not believed, But then after driving for a long time, this point of view has been verified in practice, and some people's understanding of cars still stays on the carburetor, so they still insist on the high-speed neutral block of the EFI car to save fuel.

Which fuel economy has always been a matter of debate, neutral gear and bracket coasting, in fact, both situations will save fuel but it depends on the specific situation, and it cannot be said which fuel is efficient.

The fuel-saving mechanism for coasting in neutral is that the fuel consumption is lower than in any driving state at idle. The fuel-saving mechanism of the bracket coasting is that the EFI engine will cut off the oil under the stilting condition. The low fuel consumption at idle speed is easier to understand, and the oil cut-off needs to be explained:

The EFI trip computer is roughly divided into eight working conditions to control the engine, including the supporting working condition. When the throttle is fully retracted, the throttle idle switch will be closed, and the crankshaft speed is higher than the idle state, and the trip computer will judge that the engine is in a supporting condition and stop injecting.

Oil cut-off point: The engine speed is higher than this point to enter the supporting working condition, the computer will stop the fuel injection, lower than this preset value to enter the supporting working condition to continue the oil, at this time the engine is reversed by the wheels, passive operation.

Restore the fuel injection point: To prevent the engine from stalling, the computer resumes fuel injection before the rpm drops to idle speed, allowing the engine to continue to run actively.

Emergency Fuel Injection Recovery: When the rev drops sharply, such as when braking suddenly, the trip computer will resume the fuel injection at a higher speed higher than the recovery injection point to prevent the engine from stalling, and at the same time, it can also provide more vacuum reserve for the braking boost.

The above explanation is not the same for all models, and different models or different versions of the computer will have different processing methods, which are roughly the same) Therefore, when driving:

1.If the engine speed is not high enough, coasting in neutral will be more fuel-efficient, and vice versa.

2.Gliding for long distances on horizontal roads, neutral gear is longer than supporting distance, and it is more fuel-efficient.

3.Due to the oil cut-off mechanism, the long downhill slide is more fuel-efficient than the neutral gear.

Neutral coasting is idle fuel consumption. Gear coasting, computer automatic oil cut-off, zero fuel consumption. At a certain speed, it is necessary to neutralize in order to save fuel.

In order to protect the gearbox, it is recommended to coast in gear at the current speed. Coasting in gear is more fuel-efficient than coasting in neutral gear, and there are certain safety hazards in coasting in neutral gear. The question of whether you can save fuel when coasting in neutral depends on the situation.

If not done properly, it will not only save fuel but also consume fuel. The term "neutral coasting fuel economy" comes from the old carburetor. Because the carburetor is mechanically fed, the carburetor will supply fuel as long as the engine is running, regardless of whether you are coasting or driving normally.

And if the vehicle coasts in gear, the coasting distance of the vehicle will also be shortened, so the carburetor model will definitely be more fuel-efficient to coast in neutral. When the engine speed drops to a certain extent, the engine electronic control device will not be turned off, so as to issue a control command to restart the fuel injection system and keep the engine running. The speed at which the re-injection begins is known as the "reverse injection point" of the engine.

This rev varies slightly depending on the model, but most of them are around 1200r min.

If the car is driving at high speed and the engine speed is always higher than the reverse spray point when sliding on the belt, then the engine will not spray all the time, and it needs to be sprayed in neutral gear. In this case, the belt slip is more fuel-efficient. If the car is driving at medium and low speeds, even if the gear is skidding, the engine speed will be lower than the reverse injection point, the engine will inject fuel, and the fuel injection volume will be higher than the idle fuel injection volume, so the fuel ratio of the airflow bow is better in this case.

Now, we all use electric injection engines, which are controlled by computers to supply fuel.

In order to reduce fuel consumption, the vehicle will have this setting. When you coast in gear, the engine will stop injecting fuel when the vehicle drives the engine to run passively, thus reducing fuel consumption. Airgliding:

This means taking off the landing gear and taxiing forward. In particular, neutral slippage is only for automatic transmission, and manual transmission should never be neutral. Because the manual transmission is in motion, hanging overhead, but the gearbox is still running.

Under certain braking conditions, the gears slide forward. Aim for manual and automatic transmissions, and don't coast in gear. For EFI trucks, the normal flow rate is equivalent to idle speed.

The engine still continues to be fueled. Only fuel-efficient than normal driving.

At least the surface does not show fuel efficiency.

As for what some people say about gliding farther in neutral, it depends on the purpose of the glide, if the purpose of the glide is to stop, this farther does make sense, if not, it is useless.

Coasting with gear is mostly to maintain a constant speed, and if you can't hold it, you tap the throttle. Coasting in neutral is bound to reduce speed, unless it is downhill, reduce and accelerate to the original speed, and use the saved fuel.

In most cases, coasting in neutral is more fuel-efficient than coasting in gear, because the car travels farther when coasting in neutral. The ECU can stop injecting fuel when coasting in gear, but the coasting distance is also greatly reduced.

I think it's more fuel-efficient to drive in gear than to coast in neutral with a manual transmission; Because coasting in neutral is not an appropriate operation, not only does it not save fuel, but it is also very fuel-intensive and can damage the engine.

It should be driven in gear, do not choose to slide in neutral gear, not only does not save fuel, it may cause the vehicle to slip, which may cause accidents.

<> "Manual transmission car, can you save fuel when coasting in neutral gear?"

Manual transmission clutch coasting is actually the same as neutral coasting, the power of the engine has been cut off, at this time only the engine is working at idle speed, will it be fuel-efficient? Yes! But that's just relative to when you step on the gas, which will save fuel.

It's like riding an e-bike is definitely easier than pedaling a bike, right? But this is only relative to the battery car has electricity, and it will be more tiring than the bicycle when it runs out of power.

The fuel consumption of the car is mainly due to the fact that the engine needs to burn gasoline to do work, which is to convert chemical energy into mechanical energy. The greater the engine injection, the greater the fuel consumption.

Therefore, the most fuel-consuming time is naturally the time when the throttle is deeply pressed and the acceleration is sharp or just starting, and the instantaneous fuel consumption can reach more than 10 at this time. It looks scary, but it is better to wait for the car to walk normally, and the fuel consumption will return to normal.

Why did you say that coasting in neutral or neutral would save fuel? The main thing is that stepping on the clutch is the same as neutral, at this time the engine only keeps idling to work, and the fuel consumption is very low. But this is not the same as coasting in gear during our driving.

Coasting with the clutch just saves fuel than when accelerating with the accelerator pedal.

In fact, during driving, we can also coast in gear when we don't step on the accelerator. Compared with stepping on the clutch neutral coasting, coasting with gear is the most fuel-efficient, when coasting with gear, due to the action of inertia, the engine will stop injecting, but when coasting in neutral, the engine must continue to inject fuel to maintain idling, otherwise it will turn off.

Therefore, compared to stepping on the accelerator to accelerate, coasting will be fuel-efficient. However, there are two types of gliding: sliding in band and sliding in neutral. Coasting in neutral is very dangerous, and at worst, it can even jeopardize driving safety.

And compared with coasting with gear, coasting in neutral gear is not the most fuel-efficient, and coasting with gear is the safest and most fuel-efficient practice. Stepping on the clutch and coasting will also cause clutch damage due to the possibility of incomplete clutch separation.

Therefore, everyone must not slide in neutral gear, or step on the clutch to slide. The most fuel-efficient way to do this is to coast in gear.

1. Not necessarily fuel-efficient.

2. Coasting in neutral gear of a manual transmission car does not necessarily save fuel, and may also consume more fuel.

3. In the previous automobiles, most of the injection devices used were called injectors, and their working principle was based on the air intake volume, and the oil entered the injector after hydraulic pressure, melted with air to form combustible gas, and then was sent into the air width and cylinder. So no matter which gear, as long as you use the gear stool to slide, there will be air in, correspondingly, the fuel consumption increases with the increase of air intake and gear, when changing to neutral coasting, the car's engine will be cautious to default to idle, which will indeed save fuel.

4. But now most cars are EFI trucks, and the EFI trucks release the throttle when accelerating, and the fuel injection system will stop fueling**. Therefore, if it is a manual transmission car with EFI sliding at high speed, it will save fuel, but the hanging gear will consume more fuel.