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Free-wheeling
- Thread starter snail
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Why not just use neutral?
That is what I mean by free-wheeling, putting your car into neutral.
On my car's manual it says you can free wheel simply by letting go of the accelerator, revs drop down to zero. But my bakkie will maintain revs as longs as momentum and gravity keeps me going so then i have to put it in neutral
In a fuel injected vehicle you actually use more fuel if you put it in neutral.
If you simply take your foot off the accelerator and the engine is still turning then the computer stops pumping fuel completely. If you put the car in neutral it uses fuel to keep the engine turning.
This is why most modern vehicles recommend against running in neutral. Its also much safer for controlling your vehicle and 'coasting' is also actually illegal.
If you simply take your foot off the accelerator and the engine is still turning then the computer stops pumping fuel completely. If you put the car in neutral it uses fuel to keep the engine turning.
This is why most modern vehicles recommend against running in neutral. Its also much safer for controlling your vehicle and 'coasting' is also actually illegal.
guest2013-1
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No it won't affect the engine. You'll have better economy if your car has cruise control (which I don't think you have?). Free wheeling is fine unless you're going down a very long hill and actually forget you're out of gear... happened to me more than once 
Kosmik
Honorary Master
You do however affect your brakes as far as I'm aware ie: the pressure of the hydraulics.
Only if you switch off the engine.
Kosmik
Honorary Master
I've been told coasting has the same affect as the engine is disengaged from the drive train and not powering the hydraulics.
guest2013-1
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Jase
Executive Member
To answer your question. No, it should not.
seanyp00h
Expert Member
Answer is no. But rather leave it in gear and take your foot off the accelerator. If you have an onboard computer check the consumption by going down a hill in neutral and then again in gear and you'll notice in gear you use 0l of fuel and in neutral a little more.
GforceD
Executive Member
That must mean when my car is in 5th gear the brakes work better.
Why would any sane person think the brakes are connected to the transmission.
If you turn off your car you'll lose braking and also your power steering ( and in some cars risk locking the steering wheel.)
Plus freewheeling in traffic is not very safe, if you need to avoid something or react quickly you first got to put your car in gear, and most people will want to put it in to first while moving and well that's just going to mess up your gearbox.
GforceD
Executive Member
So true my car's revs actually idle higher freewheeling in neutral than it does coasting in 4 or 5 downhill.
If fuel was not supplied as you stated, then the engine would die. Doesn't make sense.
Sinbad
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The wheels keep the engine turning. It won't die.
Modern engines use zero fuel on overrun.
HapticSimian
Honorary Master
The engine still turns - obviously - as the drivetrain transfers the rotation of the wheels to the crankshaft. As has been mentioned, you can easily confirm this yourself if your car is equipped with an on-board computer with a consumption readout.
The problem with freewheeling is that your wheels are exactly that...free, meaning they're free to spin at any velocity they want (instead of being governed by your gearbox). Thus you have less control over them when facing corners etc. Which is why it's good practice not to corner while having the clutch pressed in.
Having said that, mechanically there is no difference between freewheeling and staying idle in a traffic jam. Your brakes still work just as well as they'd work when your car is in neutral when you're in a queue or incline.
The 2-stroke comment was made because 2-stroke engines use a mixture of petrol and oil as lubrication. If you are in neutral, the engine doesn't get lubricated and you develop issues.
Having said that, mechanically there is no difference between freewheeling and staying idle in a traffic jam. Your brakes still work just as well as they'd work when your car is in neutral when you're in a queue or incline.
The 2-stroke comment was made because 2-stroke engines use a mixture of petrol and oil as lubrication. If you are in neutral, the engine doesn't get lubricated and you develop issues.