I'm saving gas

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JulesMaximus

No Lifer
Jul 3, 2003
74,580
982
126
Originally posted by: smack Down
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.

I drove manual transmission cars for over 10 years and I never once put it in neutral to coast down hill. There is absolutely no reason to do this and a couple very good reasons not to.
 

Philippine Mango

Diamond Member
Oct 29, 2004
5,594
0
0
Originally posted by: Crucial
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.

If the incline is nothing, don't expect to use engine braking then either as you'd need quite a bit of an incline to overcome engine resistance and wind resistance at that speed...
 

Midlander

Platinum Member
Dec 21, 2002
2,456
1
0
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'd like some proof. I break the law every day then. I know so many people with stick shifts that do it. wtf

See this from Tom and Ray:

Car Talk

They note that it is illegal to coast in neutral, but not to be in neutral at when stopped.
 

feralkid

Lifer
Jan 28, 2002
16,860
4,972
136
Originally posted by: DivideBYZero
Originally posted by: Hoober
Originally posted by: DivideBYZero
Originally posted by: MikeyIs4Dcats
as long as the engine is firing, you're still burning gas

No. My foot isn't on the gas pedal.

Then what's firing the combustion? :roll:

There isn't any. My foot is off the gas and the car is in neutral.

Turn off the ignition you coward.
 

DivideBYZero

Lifer
May 18, 2001
24,117
2
0
Originally posted by: loic2003
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

But I'm saving gas.
 

sonoma1993

Diamond Member
May 31, 2004
3,414
21
81
Originally posted by: DivideBYZero
Originally posted by: loic2003
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

But I'm saving gas.

you sir are an Idiot
 

Ragnarok2

Senior member
Jul 11, 2006
534
0
0
Originally posted by: DivideBYZero
Originally posted by: Hoober
Originally posted by: DivideBYZero
Originally posted by: MikeyIs4Dcats
as long as the engine is firing, you're still burning gas

No. My foot isn't on the gas pedal.

Then what's firing the combustion? :roll:

There isn't any. My foot is off the gas and the car is in neutral.

You're the guy that made fun of me for wanting to put in a cold air intake in my car. Now, I laugh at you. Pal, unless your engine is off, then its using gas. That means it uses gas when its park as well as when its in neutral. Simple as that. In neutral the engine still rev's at 1000-2000rpm. When you press the gas pedal it gives the engine more gas and it revolves a lot more. Damn I feel like I'm giving a speech to my 4 year old sister.
 

DivideBYZero

Lifer
May 18, 2001
24,117
2
0
Originally posted by: Ragnarok2
Originally posted by: DivideBYZero
Originally posted by: Hoober
Originally posted by: DivideBYZero
Originally posted by: MikeyIs4Dcats
as long as the engine is firing, you're still burning gas

No. My foot isn't on the gas pedal.

Then what's firing the combustion? :roll:

There isn't any. My foot is off the gas and the car is in neutral.

You're the guy that made fun of me for wanting to put in a cold air intake in my car. Now, I laugh at you. Pal, unless your engine is off, then its using gas. That means it uses gas when its park as well as when its in neutral. Simple as that. In neutral the engine still rev's at 1000-2000rpm. When you press the gas pedal it gives the engine more gas and it revolves a lot more. Damn I feel like I'm giving a speech to my 4 year old sister.

Try reading the whole thread and then see how superior you feel...
 

nakedfrog

No Lifer
Apr 3, 2001
62,785
18,980
136
Originally posted by: Ragnarok2
You're the guy that made fun of me for wanting to put in a cold air intake in my car. Now, I laugh at you. Pal, unless your engine is off, then its using gas. That means it uses gas when its park as well as when its in neutral. Simple as that. In neutral the engine still rev's at 1000-2000rpm. When you press the gas pedal it gives the engine more gas and it revolves a lot more. Damn I feel like I'm giving a speech to my 4 year old sister.

Your idle is set too high. You're wasting gas.
 

AlienCraft

Lifer
Nov 23, 2002
10,539
0
0
Originally posted by: DivideBYZero
Originally posted by: Hoober
Originally posted by: DivideBYZero
Originally posted by: MikeyIs4Dcats
as long as the engine is firing, you're still burning gas

No. My foot isn't on the gas pedal.

Then what's firing the combustion? :roll:

There isn't any. My foot is off the gas and the car is in neutral.

The engine doesn't quit running simply because your foot isn't applying throttle.
You are aware of the concept of "idle running" ,are you not?
 

91TTZ

Lifer
Jan 31, 2005
14,374
1
0
Originally posted by: Mark R

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.

It's true that the ECU will stop injecting fuel while doing this, but you still incur the efficiency losses by turning the engine when it's off, as compared to just coasting in neutral. In other words, engine braking still works when the engine is off. You'll drain speed by doing it, so you lose momentum. Then when you need to accelerate again, you'll have to use more gas to reach your original speed.

Or, to simplify it- it doesn't use any gas at all to hit your brakes, but in the long run it does use gas... because you'll need to gain back that speed you just lost.
 

nakedfrog

No Lifer
Apr 3, 2001
62,785
18,980
136
Originally posted by: 91TTZ
Originally posted by: meltdown75
I have a craving for some chicken pot pie.

Now that you mention it, I do too.

I wish I could find more meat-lover's chicken pot pie. It was all chicken, none of those pesky peas or carrots or what-have-you.
 

Midlander

Platinum Member
Dec 21, 2002
2,456
1
0
Originally posted by: Acanthus
Originally posted by: DivideBYZero
Originally posted by: Hoober
Originally posted by: DivideBYZero
Originally posted by: MikeyIs4Dcats
as long as the engine is firing, you're still burning gas

No. My foot isn't on the gas pedal.

Then what's firing the combustion? :roll:

There isn't any. My foot is off the gas and the car is in neutral.

LMAO :D

At some point, he will reread what he wrote and smack his forehead. D'oh.
 

AgaBoogaBoo

Lifer
Feb 16, 2003
26,108
5
81
I love how we have these threads over and over again, it's always the same stupid questions. Answers are quickly revealed, but some people *never* want to change how they think...