EFI gasoline car downhill hanging neutral gear is fuel efficient

There is a function called the reverse towing function in the ** control processor (ECU) of the injection engine, that is to say, under normal circumstances, the engine provides forward power to the vehicle, and the engine effectively controls the speed of the vehicle when the reverse trailer is reversed, and its control function is realized by the joint action of the engine speed sensor and the throttle position sensor. When the speed is relatively high, release the accelerator pedal, at this time the throttle position sensor outputs the signal of the idle position, and the engine should enter the idle working condition, but because the transmission is not in neutral, the inertia of the vehicle drags the engine to a higher speed instead of the standard idle speed, and the ECU of the EFI engine will judge the actual working condition of the engine according to the different signals of the throttle and crankshaft position sensors, and no longer provide fuel to the engine when the signal is not working, so as to achieve the purpose of saving fuel. If the neutral coast is running, the engine will always receive information that it is working, and the fuel supply system will continuously supply fuel to the engine, which will increase fuel consumption.

It is not fuel-efficient, it does not cost fuel, and it is the same as usual, and now it is an EFI truck, and you go downhill and hang in neutral, it is easy to die, and even the brakes can't be burned, which is more dangerous.

It must cost fuel, EFI cars, coasting with gears is the most fuel-efficient, and the computer-controlled fuel injection system with gears coasting stops supplying fuel.

It is not fuel-efficient, and it burns oil when idling, and it does not inject fuel without taking off the gear.

Fuel Efficient! It also has a great impact on the braking system!

Fuel-saving with gear! It's safe, too! But the premise is that the throttle is fully closed and the engine speed is above 1800 rpm, then there is no fuel injection, that is, the fuel consumption is zero!

The EFI truck slides downhill and is fuel-efficient. Don't slide in neutral, it's dangerous, these experiences are all exchanged for the lives of the predecessors.

Coasting in neutral saves fuel.

Neutral coasting refers to: in the driving of a motor vehicle, the driver puts the gear lever in the neutral position, separates the engine from the clutch of the driving wheel, and uses the operation method of vehicle inertia to drive.

Neutral coasting must be carried out under the condition of ensuring safety and the technical condition of the vehicle, and it is not allowed to turn off the ignition and slide, especially when descending a steep or long slope.

When coasting in neutral, the engine is in a state of low fuel consumption at idle speed, and the vehicle continues to drive, so fuel economy is achieved.

For EFI engines, the throttle sensor operates in 3 states: idle, partial-load, and maximum-loaded. In the partial load zone, the throttle sensor is able to collect both position and rate of change signals, that is, the same throttle opening change, the slow acceleration of the throttle and the sharp acceleration of the throttle are different, and the engine reacts differently.

The EFI truck is fuel-efficient and safe to slide in gear.

The long downhill is definitely fuel efficient in neutral!

But it's not safe!

August 3, 2018 16:33:45, the problem has been after mine (reduce my rate, thankless):

Didn't answer the main point, and the text was not right. The question is that the engine does not inject fuel, although the car has an inertia speed, but if the oil is below the ignition point, and the ejected oil has burned out, will this not stall?

It stands to reason that when going downhill, the engine is not injected with fuel, which is in a state of flameout.

So the crux of the matter is:

When the engine is flamed off and has a high speed, can direct fuel injection reach the ignition point? Like how do you light a match after it is blown out by the wind?

If it can't fire automatically, then the EFI engine must be powered up with a spark plug at the same time as the fuel injection to re-ignite the stalled engine when the rpm drops below a certain value, right?

In fact, when the engine is driven at sufficient speed, direct fuel injection can reach the ignition point. Here's how it works:

The EFI engine monitors that the speed is lower than a certain value, the fuel injection atomizes and the mixed air enters the combustion chamber, at this time the intake valve and exhaust valve are closed, the engine compresses the stroke, the mixed gas is compressed and heats up sharply, reaching the ignition point of gasoline, which is the conversion of mechanical energy into internal energy, at this time the engine is successfully ignited, the gas expands after ignition, pushes the piston, and the internal energy is converted into mechanical energy, and the cycle repeats.

If you see it, please like it!

The EFI vehicle slides downhill with gear, there is a certain speed, and the speed produces inertia, which is the main reason why the vehicle will not turn off even if the engine does not inject fuel when driving by inertia.

The above master is very auspicious, in short, do not hang neutral gear down the steep slope, safe and fuel-efficient, not EFI is also fuel-efficient, because the power engine is driven by the inertia of the vehicle, and the fuel supply is also zero under the effect of speed regulation, so there is no need to consume fuel at all!

It's very good ... I don't need to say more.

In the case that the gearbox does not hang neutral, it is by the inertia of the vehicle, the anti-drag engine to keep it running, usually when the engine speed drops to about 1500 rpm, in order to prevent the engine from stalling, the computer resumes the fuel supply.

In the case of the gearbox in neutral gear, if the engine speed is higher than 1500, and the throttle is in the closed state, the engine computer also stops supplying oil, at this time the engine speed will inevitably decrease, when it drops to about 1500 rpm, the oil supply is resumed, and the power to maintain the engine operation is self-evident, it is the rotational inertia of the engine itself.

1. The neutral coasting of the EFI engine will not only not save fuel, but also consume more fuel to a certain extent. According to the principle of the engine, the EFI engine can judge the amount of fuel injected according to the computer program. In the case of gearing, if the owner releases the throttle, the computer will let the car enter coasting mode, and for a long time, the engine is not injected; If you coast in neutral, the computer will put the car into idle mode and the engine will still be injected.

Second, for automatic cars, there can be no neutral (N-gear) coasting operation. Oil pump - oil pressure - gearbox work, this is the basic working principle of automatic transmission, if the neutral gear slides, it is equivalent to moving the foot away without the accelerator, cutting off the oil supply, at this time the gearbox becomes dry friction, for a long time, not to mention fuel saving, the gearbox may be wasted. Therefore, the car with automatic transmission must not coast in neutral gear.

Fuel efficient. Because when it's downhill, it's obvious.

First of all, downhill neutral coasting is not safe, but also can not play the role of fuel saving, the current EFI car fuel injectors are controlled by the driving computer through the bus, with gear downhill sliding due to the load reduction, the computer will automatically issue instructions to stop fuel injection, at this time the engine crankshaft is driven by the car's own inertia force and gravity along the direction of the ramp, at this time fuel consumption can be regarded as zero.

When hanging neutral, due to the disconnection of the power connection between the engine and the gearbox and the chassis drive part, in order to ensure the normal operation of the engine (not stalling), the engine must be injected with fuel to ensure idle operation, and the fuel consumption at this time is equivalent to or slightly lower than that when idling in situ.

Although it may seem like you can slide very far downhill in neutral, it is actually dangerous (the longitudinal lack of engine power and traction, and it is easy to lose control in sharp corners) and is no more fuel-efficient than coasting in gear.

The neutral block is not fuel-efficient, and the computer adjusts the fuel supply according to the speed, water temperature, etc.

The engine of the car, when it is given oil, it will output power to the car. If you don't give oil, it will have a resistance to the car, which we call the engine braking force. Drivers can try it, the manual gear handlebar clutch to the end, the automatic car hang N gear, see if the car is very "slippery", relative to the gear does not step on the accelerator.

Or when you are at 50 speed, go to 2nd gear, the car will slow down all of a sudden, and the person will rush forward.

The braking power of the engine has a very big advantage compared to the brakes, because it does not act directly on the wheels, so it does not cause the car to slip sideways when braking.

Especially when going downhill, be sure to use engine braking power. Because if you use the brake to keep pressing, after a period of time, the brake pads (leather) will reduce the braking efficiency due to heating, and even become no brake, so you must hang a gear and use the engine braking force to control the speed. Brakes as an assist.

Of course, the braking power of the engine should not be used excessively, as this may damage the engine or gearbox.

When coasting in neutral, the braking effect must not be as obvious as when the gear is in gear. So don't coast in neutral.

Neutral pulleys are not fuel-efficient. The computer adjusts the fuel supply according to the vehicle speed, water temperature, etc.

It depends on the distance. If it is long, it is in the neutral space. If it's short, it's fuel-efficient with gear.

Upstairs is plagiarized, I can find that the current cars are basically EFI technology. On long-distance downhill roads, driving in gear can save fuel!

Because at this time, the engine is not injected, because the computer detects that the position of the throttle sensor is very small, but the actual speed is relatively high, so the computer stops supplying fuel to the engine, so the fuel consumption is 0 or close to 0!

Once you drive in neutral, the engine will enter the idle condition, even if you fully lift the accelerator pedal, the engine is still running, at this time it will consume fuel, and the mixing of idle conditions is larger, so fuel consumption can not be ignored.

Of course, it doesn't cost fuel to switch to a sliding form, but it's very dangerous, because the brake boost will fail, and the steering power will also fail, and there is a possibility of steering lockup. The vehicle itself is equipped with a safety system that fails: ABS

And the electronic stability system or something is useless. In the event of an emergency, that.

The correct way is not to be in neutral, just OK

Today's cars are all EFI engines, and the neutral gear is not fuel-efficient at all, and the starting chain is the opposite, which will also hinder the braking system and cause brake failure. The old driver said that the number of fuel saving was because the cars at that time still used carburetors, so they were fuel-saving in neutral.

The electric injection car downhill with gear Tanxiao sliding, there is a certain speed, the speed produces inertia to stop the spike, even if the engine is not simply injected when the vehicle is driving by inertia, it will not turn off the main reason.

In the case that the gearbox does not hang neutral gear, Chunshan relies on the inertia of the vehicle to reverse the drag engine to keep it running, usually when the engine speed drops to about 1500 rpm, in order to prevent the engine from stalling, the computer resumes the fuel supply.

In the case of the gearbox in neutral gear, if the engine speed is higher than 1500, and the throttle is closed, the engine computer also stops supplying oil, at this time the engine speed will inevitably drop, when it drops to about 1500 rpm, the oil supply is resumed, and the power to maintain the operation of the engine is self-evident, it is self-evident that the engine itself rotates and the inertia of the engine itself.