I'm saving gas

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cheapgoose

Diamond Member
May 13, 2002
3,877
0
0
Originally posted by: DivideBYZero
Going on a long journey I like to save as much gas as I can. I've been putting the car into neutral when coasting or going down a fairly long descent to save as much gas as possible.

I expect I save about a gallon a month doing this.

It's an MT, BTW.

well, I don't know about your car, but when I'm in neutral, the engine rev is the same as if I was in drive. When rolling downhill.
 

pray4mojo

Diamond Member
Mar 8, 2003
3,647
0
0
You can save more fuel by putting your car on a conveyor belt and letting it take off.
 

DivideBYZero

Lifer
May 18, 2001
24,117
2
0
Originally posted by: d3n
I sometimes down shift when going down hill to let the engine do the breaking. Thats another topic I imagine.

Yeah, it is. Doing that uses fuel. I save gas by putting the car into neutral.
 

Philippine Mango

Diamond Member
Oct 29, 2004
5,594
0
0
Originally posted by: MercenaryForHire
THIS THREAD IS NOW ABOUT PIE.

- M4H

Apple or cranberry? Cause I hate cranberries, the food and band, both suck and both should be burned at 451*F along with that crappy book...
 

Philippine Mango

Diamond Member
Oct 29, 2004
5,594
0
0
Originally posted by: cheapgoose
Originally posted by: DivideBYZero
Going on a long journey I like to save as much gas as I can. I've been putting the car into neutral when coasting or going down a fairly long descent to save as much gas as possible.

I expect I save about a gallon a month doing this.

It's an MT, BTW.

well, I don't know about your car, but when I'm in neutral, the engine rev is the same as if I was in drive. When rolling downhill.

Do you have an automatic? Believe it or not but when you're rolling down a hill in the highest gear, the tranny cuts out and goes basically into neutral (I've experience this many times) and I can feel the friction point with the tranny slightly catching on, matching syncros and then finnally outputting real power to the drivetrain when I hit the gas. (Forgot to clarify that)

best thing to do is use enough engine braking so that you're going a reasonable speed with out riding the brakes but not so much as to grind your car to a hault or 10mph... I'm sure you kiddies are smart enough to figure out when to shift into 3rd, 2nd and 1st gear...
 

nakedfrog

No Lifer
Apr 3, 2001
62,785
18,982
136
Originally posted by: MercenaryForHire
THIS THREAD IS NOW ABOUT PIE.

- M4H

Think of all the gas you can save on your way to the store to buy pie using this revolutionary technique!
 

randay

Lifer
May 30, 2006
11,018
216
106
I got 132 mpg out of my engine today by coasting!














too bad I usually get 150 mpg by staying in gear. :(
 

Mark R

Diamond Member
Oct 9, 1999
8,513
16
81
Originally posted by: DivideBYZero
Originally posted by: JulesMaximus
Coasting downhill is not going to save you any fuel whatsoever. When coasting in gear you are using zero gas anyway. Coasting in neutral you are actually using fuel to keep the engine at idle.

No. If I coast in gear the engine will turn and I will lose fuel. :(

Not in a modern car.

In a modern car, the ECU will sense the car's speed and recognise the fact that it is in gear - and that the car's rolling momentum will keep the engine turning. The fact that the car's momentum is enough to keep the engine going allows the ECU to shut off the fuel completely during engine breaking.

When the car slows down to just above idle, the ECU will turn the fuel back on.

If you switch to neutral, there's no momentum connected to the engine to keep it turning - this means the engine has to keep turning under its own power. This means it needs fuel, and the ECU will continue to deliever fuel to it.

You will use more fuel coasting in neutral than coasting in gear, for this reason.

 

fbrdphreak

Lifer
Apr 17, 2004
17,555
1
0
Oh jesus not this discussion again....I'll look for ZV's shutdown post...

EDIT Nevermind, I call for a lock and vacation
 

gsethi

Diamond Member
Feb 28, 2002
3,457
5
81
Instead of coasting in neutral, take the shortest route (aka jumping off the cliff). I will guarantee that the "shortest" route will save you the most gas :p (in some cases, you might never need gas anymore ;) )
 

waggy

No Lifer
Dec 14, 2000
68,143
10
81
a better way way to save gas is have these nic strong treadmills that can keep a jet plane from takeing off all over the U.S.
that way we save gas! and AIR pollution! not to mention the sky will be clear because there are no planes in the sky.
 

jagec

Lifer
Apr 30, 2004
24,442
6
81
Originally posted by: Amused
This is illegal for the main reason that if your car stalls (it is more likely to stall at idle) you lose power steering and power brakes.

Some people are even more stupid and suggest shutting the car off when coasting, ensuring that they lose power steering and power breaks.

Both are bad ideas.

To be fair, neither power steering nor power brakes are essential. The brakes are kinda nice, though...the pedal's REALLY stiff without them.
 

Strk

Lifer
Nov 23, 2003
10,197
4
76
For those who can't figure out that a car is using gas while not in gear, go start a car without gas and see how far you get.
 

Crucial

Diamond Member
Dec 21, 2000
5,026
0
71
Originally posted by: Philippine Mango
Originally posted by: Crucial
When I coast down hill I lose speed. The only way I can maintain speed is by pressing the accelerator. If I push in the clutch I will maintain speed or gain speed on the same hill. Explain to me how the ECU can cut off fuel if I have to press the accelerator to maintain speed? At speed the revs are around 1800. Coasting with clutch in revs are 800.

If you have to press the accelerator then you're an idiot. You're using "too much" engine braking, switch to a higher gear... Only press the accelerator when going down the hill if you prefer to coast at a slower speed but end up having some dumbass come up behind you riding your ass on the way down...

Car doesn't have anything higher than 5th gear. This is at 60mph on the freeway.
 

animalia

Banned
Dec 15, 2006
792
0
0
Originally posted by: Rob9874
Originally posted by: Shawn
stupid. plus it's illegal. at least in the US anyway.

Illegal to coast in neutral?

yeah, I'd like some proof. I break the law every day then. I know so many people with stick shifts that do it. wtf
 

udonoogen

Diamond Member
Dec 28, 2001
3,243
0
76
Originally posted by: nakedfrog
Originally posted by: Phoenix86
Originally posted by: nakedfrog
Originally posted by: DivideBYZero
Originally posted by: nakedfrog
:laugh:
You smarmy bastard. I know what you're doing.
*looks closely at DBZ's avatar*

You just want to be a 'HYPERMILER' like me. :p

True, I also hope to save fuel. In bulk.

Would you sell the bulk fuel? online?

Yes, but you'd have to buy it in at least alternator-sized amounts. I think that's around 10lb.

wonder if they can combine shipping with the folks that ship my beef
 

DivideBYZero

Lifer
May 18, 2001
24,117
2
0
Originally posted by: Strk
For those who can't figure out that a car is using gas while not in gear, go start a car without gas and see how far you get.

I coasted down my street for about 2 miles. I saved 2 miles worth of gas thanks to your tip. :thumbsup:
 

loic2003

Diamond Member
Sep 14, 2003
3,844
0
0
Modern cars with electronic ignition use less fuel if you have it in gear and have momentum turn the engine over instead of it requiring fuel. Putting it in neutral will use more fuel, and give you less control of the car
 

Zero001

Member
Jan 6, 2007
154
0
71
Originally posted by: DivideBYZero
I'm going to drive with all the windows down, too, to save on A/C.

Studies have shown that if you drive with your windows down at speeds over 55mph, you waste more gas than with the windows up and A/C the on because of the increase in drag.
 

Scouzer

Lifer
Jun 3, 2001
10,358
5
0
Originally posted by: Mark R
Originally posted by: DivideBYZero
Originally posted by: JulesMaximus
Coasting downhill is not going to save you any fuel whatsoever. When coasting in gear you are using zero gas anyway. Coasting in neutral you are actually using fuel to keep the engine at idle.

No. If I coast in gear the engine will turn and I will lose fuel. :(

Not in a modern car.

In a modern car, the ECU will sense the car's speed and recognise the fact that it is in gear - and that the car's rolling momentum will keep the engine turning. The fact that the car's momentum is enough to keep the engine going allows the ECU to shut off the fuel completely during engine breaking.

When the car slows down to just above idle, the ECU will turn the fuel back on.

If you switch to neutral, there's no momentum connected to the engine to keep it turning - this means the engine has to keep turning under its own power. This means it needs fuel, and the ECU will continue to deliever fuel to it.

You will use more fuel coasting in neutral than coasting in gear, for this reason.

Yeah. My Pontiac Pursuit has the on board fuel economy thing I can reset at anytime.

Before it's dismissed, I've tracked it on 4 separate tanks of gas and it's always been within .1 mpg of my actual fuel usage.

If I coast in gear, then reset the fuel economy calculator, it's using zero gas.
 

JulesMaximus

No Lifer
Jul 3, 2003
74,580
982
126
Originally posted by: animalia
Originally posted by: Rob9874
Originally posted by: Shawn
stupid. plus it's illegal. at least in the US anyway.

Illegal to coast in neutral?

yeah, I don't know how to drive. Did I mention that I don't know how to drive? I know so many people who also don't know how to drive. wtf

Fixed.
 

smack Down

Diamond Member
Sep 10, 2005
4,507
0
0
If the hill isn't steep enough and requires the accelerator to maintain your speed then you would save gas in neutral. If the hill so steep that breaking (engine or otherwise) is required then you will use more gas to coast in neutral.