I assumed that they're talking about shifting the car into neutral and then shutting the car off.
Shutting it off while in drive just makes it sound even more dumb than it is. Please tell me that's not what is happening.
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Being in neutral while moveing
- Thread starter graver555
- Start date
I assumed that they're talking about shifting the car into neutral and then shutting the car off.
Shutting it off while in drive just makes it sound even more dumb than it is. Please tell me that's not what is happening.
There has been talk in this thread about shutting the ignition of the vehicle OFF while driving. It started at post #20...
There has been talk in this thread about shutting the ignition of the vehicle OFF while driving. It started at post #20...
That's life-threatening nonsense.
It's also not required to save fuel when going down a hill.
Hey I couldn't expect the thread to jump shark. The last thing I've seen was bassman1958s very reasonable post. You don't have to turn the engine off to get the savings.
Actually many drivers will do this. I do not advocate it nor on any regularity do it but many do. It will save even more fuel then just coasting in neutral.
Also while I am not very up to date with news I have not heard of someone getting rear ended due to coasting. If you have any news articles of this I would be happy to read them.
It's kind of odd that people are so against this - I got stuck with no cash and a *very* low fuel tank the other week and needed to get to work and home (15kms each way) on as little fuel as possible, so I used the same rationale as the OP -
Accelerate up to speed, identify where your next intersection is and take a guess at how much momentum you need to get you there by coasting. Instead of braking late, you start slowing down early instead, if you gauge it just right, no braking is required at the intersection. I drive a manual, so when I need to get back into gear, pick one to suit, rev match, click it in and off you go smooth as.
It got me thinking about how much fuel it actually saves, so I did a very rudimentary unscientific economy test, and managed about 320kms from my tanks halfway point deliberately trying to optimise time spent in neutral, where I usually get 250kms with normal driving (all values are approximates).
With regards to the safety aspect, if you are going to drive unsafely you shouldn't be on the road. Is this an unsafe practice? It depends - I drive country roads to work with little to no traffic, and the terrain is extremely flat, so I don't have to contend with hills. If there is other traffic around, I will change my habit to a more traditional style of driving, but so long as there's noone around, me coasting slowly to intersections is hardly unsafe.
PS I can't advocate switching off the engine while coasting, particularly on newer cars where I find you lose power steering, and some braking ability
Accelerate up to speed, identify where your next intersection is and take a guess at how much momentum you need to get you there by coasting. Instead of braking late, you start slowing down early instead, if you gauge it just right, no braking is required at the intersection. I drive a manual, so when I need to get back into gear, pick one to suit, rev match, click it in and off you go smooth as.
It got me thinking about how much fuel it actually saves, so I did a very rudimentary unscientific economy test, and managed about 320kms from my tanks halfway point deliberately trying to optimise time spent in neutral, where I usually get 250kms with normal driving (all values are approximates).
With regards to the safety aspect, if you are going to drive unsafely you shouldn't be on the road. Is this an unsafe practice? It depends - I drive country roads to work with little to no traffic, and the terrain is extremely flat, so I don't have to contend with hills. If there is other traffic around, I will change my habit to a more traditional style of driving, but so long as there's noone around, me coasting slowly to intersections is hardly unsafe.
PS I can't advocate switching off the engine while coasting, particularly on newer cars where I find you lose power steering, and some braking ability
There has been talk in this thread about shutting the ignition of the vehicle OFF while driving. It started at post #20...
Actually it started in post #19
Read the last line of that post!
This.
Almost the exact same situation except with an automatic. I was a bit cautious first time shifting back into gear while moving it turns out as long as my foot is off the gas it matches revs itself and the torque converter puts enough give in the system that nothing bad happens as long as Im not reving.
I can't remember the last time that I saw/read something in the news related to a relatively minor car accident. If people didn't die or the car didn't explode into flames nobody cares...
My car has two "live" fuel usage displays, one is a "right now" needle and then there is a counter that you can reset at all. After getting the car I used it extensively for such tests.
Going down a smooth hill in neutral, engine idling, the consumption easily goes > 99 mpg, which is the display's maximum.
Going down the same hill in 5th gear you get about 40. The problem is that the hill isn't steep enough to push the engine into shutting off the fuel supply, you need a much steeper hill for that, then you would get infinity mpg.
The problem is that not being in neutral on these hill some sections make you lose too much speed from dragging around all the machinery and you actually need to give it a little gas pedal. Then you are at 30 mpg, and that is the same hill you could coast in neutral.
So there are real savings here even without turning off the engine. I stopped doing this because of concerns that the (automatic) transmission doesn't like going in and out of neutral when moving. The manufacturers are clear that it voids the warranty, which might or might not point to a real technical problem with it.
Somebody still needs to explain to me why somebody would possibly get rear-ended due to coasting.
The deceleration in neutral is much less than simply taking the foot of the gas, the latter braking the car through transmission and engine. Brake lights are off in either case.
I really wish I had a fuel usage display on my car
I have to go by top it off and see how much it took to go x miles.I did have a concern about whether it was bad for the trany but I havnt heard any complaints coming from it unless the engine is above an idle. However I do wait for the engine to warm up before I start coasting as before that it does some weird things when I try. But by this time I am out of my small town where it really helps anyway :/
I did some research on them and I know that they can be flat towed in neutral so I dont have to worrry about the engine providing lubrication. (although Im not sure if it still does in neutral?)
I really wish I had a fuel usage display on my car
I did have a concern about whether it was bad for the trany but I havnt heard any complaints coming from it unless the engine is above an idle. However I do wait for the engine to warm up before I start coasting as before that it does some weird things when I try. But by this time I am out of my small town where it really helps anyway :/
I did some research on them and I know that they can be flat towed in neutral so I dont have to worrry about the engine providing lubrication. (although Im not sure if it still does in neutral?)
Scan gauge or ultra gauge
I meant to say the coastee could do the read ending...not get rear ended.
You're coming to a stop light
There is a car in front of you
You decide to coast to the light in neutral
The car in front stops abruptly and very short
Not enough time to brake, you'd rear end them anyways, hitting the gas in the best option
Oops, I forgot I was in neutral...crunch
You're coming to a stop light
There is a car in front of you
You decide to coast to the light in neutral
The car in front stops abruptly and very short
Not enough time to brake, you'd rear end them anyways, hitting the gas in the best option
Oops, I forgot I was in neutral...crunch
Umm..... Hitting the gas as your about to rear end somebody achieves?
Oh you mean to either switch lanes (probably hitting someone else instead) or hitting the shoulder, well I don't see how hitting the gas will get you to the shoulder any easier..
Just let it go, neutral isnt a a big deal, cutting off the engine ok maybe.. But neutral? No?
And I can put my car in drivejust as fast as you can take your foot off a clutch, so, manuals should be illegal?
Good
Thing my car uses NO fuel coasting in gear..
Also if your idling its more effecient to be in neutral, thankfully my DSG transmission does this automatically.
For most cars, starting the engine consumes a non-trivial amount of fuel, not to mention that's when most of an engine's wear occurs. Turning off your ignition is likely doing the opposite of what people think while shortening the overall life of the vehicle.
Also for most automatic vehicles, shifting from neutral to drive while coasting causes some transmission internals to immediately go from standstill to full speed. This may not make a notable jolt or horrible sound when done each time, but it will one day end the party earlier than just driving as the car was designed.
I don't really understand the claims of cars "shutting off the fuel supply" and "infinity" fuel economy. An idling engine is burning fuel. Maybe a small amount, but there is fuel flowing.
One more point, gasoline's physical volume fluctuates rapidly with temperature. It takes up more space when hot, less when cold. Using the fill up and odometer to measure mileage is definitely unscientific, but is probably close enough for our personal averages. To get a little more for your money, try to fill up in morning when the underground tanks are their coolest.
Also for most automatic vehicles, shifting from neutral to drive while coasting causes some transmission internals to immediately go from standstill to full speed. This may not make a notable jolt or horrible sound when done each time, but it will one day end the party earlier than just driving as the car was designed.
I don't really understand the claims of cars "shutting off the fuel supply" and "infinity" fuel economy. An idling engine is burning fuel. Maybe a small amount, but there is fuel flowing.
One more point, gasoline's physical volume fluctuates rapidly with temperature. It takes up more space when hot, less when cold. Using the fill up and odometer to measure mileage is definitely unscientific, but is probably close enough for our personal averages. To get a little more for your money, try to fill up in morning when the underground tanks are their coolest.
