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I'm saving gas

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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.
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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.
 
Originally posted by: d3n
I sometimes down shift when going down hill to let the engine do the breaking. Thats another topic I imagine.
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Yeah, it is. Doing that uses fuel. I save gas by putting the car into neutral.
 
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.
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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.
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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...
 
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.
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No. If I coast in gear the engine will turn and I will lose fuel. 🙁
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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.

 
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 😛 (in some cases, you might never need gas anymore 😉 )
 
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.
 
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.
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To be fair, neither power steering nor power brakes are essential. The brakes are kinda nice, though...the pedal's REALLY stiff without them.
 
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.
 
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.
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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...
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Car doesn't have anything higher than 5th gear. This is at 60mph on the freeway.
 
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*
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You just want to be a 'HYPERMILER' like me. 😛
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True, I also hope to save fuel. In bulk.
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Would you sell the bulk fuel? online?
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Yes, but you'd have to buy it in at least alternator-sized amounts. I think that's around 10lb.
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wonder if they can combine shipping with the folks that ship my beef
 
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.
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I coasted down my street for about 2 miles. I saved 2 miles worth of gas thanks to your tip. :thumbsup:
 
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
 
Originally posted by: DivideBYZero
I'm going to drive with all the windows down, too, to save on A/C.
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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.
 
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.
Click to expand...

No. If I coast in gear the engine will turn and I will lose fuel. 🙁
Click to expand...

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.
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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.
 
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.
 
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