Why can't the vehicle roll in neutral?

I think many people have said that the vehicle cannot slide in neutral when they are learning to drive, driving school instructors and driving tests. There are two main reasons for this.

One is that the current vehicle engines all use electronic fuel injection technology, which can ensure that the vehicle does not inject or inject less fuel when the vehicle is sliding with a gear. And if you are coasting in neutral gear, the engine will be regarded as idling, but more fuel will be injected than when you are coasting with gear, which will waste more than one star and a half of fuel in the long run.

The second reason is that sliding in neutral gear is extremely dangerous. Under downhill road conditions, when the vehicle is fully loaded, the chassis transmission mechanism is not connected to the engine due to sliding in neutral gear. At this time, not only the traction force of the engine is lost, but also the engine and auxiliary brakes are lost. The braking force of the brake is only used to control the speed of the vehicle.

In this context, when the vehicle encounters danger and needs to brake urgently, not only the braking effect will be sharply reduced, but also the vehicle will lose its balance and cause the vehicle to drift.

In order to pursue fuel-efficient driving, many drivers have the driving habit of high gear and low speed, and always keep the engine running at the lowest speed limit of the economic speed range. The most obvious phenomenon is that when you finish shifting, the engine speed immediately It fell off. At this time, in order to ensure the power, you have to step on the accelerator to increase the speed.

This behavior can also be called dragging. After a long-term occurrence, it will easily lead to the formation of carbon deposits inside the engine, which has a great impact on engine life and fuel consumption. At the same time, this behavior will also cause the engine power to drop and the forward to be weak, so it is not advisable to drag the gear for a long time, and it will not have a good performance in terms of fuel economy.

Some drivers think that the smaller the rolling resistance of the tires, the better the tire pressure is, so that the resistance is small and it is helpful to save fuel. driving hazard.

1. After the tire pressure is too high, the driving experience will become worse. In short, the vehicle will be more bumpy and the fuel consumption will increase. And in this case, the workload of the chassis suspension will be increased, and the service life of the suspension components will be deteriorated.

2. Excessive tire pressure will increase the risk of tire blowout, especially in high-speed and high-temperature scenarios. and it also affects the braking effect

3. If the tire pressure is too high, the center of the tire surface will wear too fast, and both sides of the tread will wear slowly, which will aggravate and reduce the service life of the tire. At the same time, because the contact surface is too small, the braking distance will be increased, which is easy to cause accidents.

From the above point of view, high tire pressure may not only lead to high costs, but also endanger our lives. In addition, too low tire pressure is not a good thing, and it will also increase tire wear, so when you adjust the tire pressure, you need to increase or decrease it in strict accordance with the tire pressure parameters at the factory.