I read some online "advice" about coasting in neutral in order to save on gas. That doesn't sound like a good idea to me.

I see 2 major problems with this:

1. It's not safe and, in most states/provinces, it's illegal to coast in neutral. In short, the ability to react to road conditions is more limited in neutral.

2. Shifting to neutral and shifting back to a gear must cause stress on transmission especially when driving at higher speeds.

Those who argue in favor of coasting in neutral say they do this only when it's really safe, like in the middle of nowhere. They also claim no damage to transmission. Anyone does this on a regular basis?

I agree 100%

From Popular Mechanic magazine :

Does Shifting Into Neutral Really Help Fuel Economy?

By Mike Allen
Published in the December 2007 issue.




Q: I have a question about fuel economy. If you are driving downhill, do you save gas by putting your transmission in Neutral and coasting, instead of having your vehicle in Drive? I think that you do but my wife seems to disagree. Can you give me the correct answer, so I can tell her that I’m “Mr. Right,” as usual?

A: That depends. The engine isn’t braking the car going downhill if the transmission is in Neutral, so economy would seem to be high. But if you think the engine is still using fuel while coasting downhill in gear, you’re laboring under a misconception. Most fuel-injected cars turn the fuel delivery completely off when you lift your foot from the accelerator. They still burn fuel when idling in Neutral, so do the math. The amount of fuel burned at idle over, say, a couple of miles of coasting downhill is small, but it’s still more than zero. So if you’re driving a modern fuel-injected car, you’re wrong.
Older, carbureted cars would suck gas through the engine while coasting in gear, even if you turned off the ignition switch. In this case you’d be right.

Welcome to last week: To coast or not to coast.

It's not rocket science to figure out where one can safely coast in neutral. I have done it -- and lived to tell.

And if you are not comfortable with the idea... then don't do it.

We as a country, in relation to our use of fossil fuels and foreign oil, will either adapt or perish.

The folks who drive differently to use less fuel are simply not waiting for anyone else, especially da Gubbermint, to tell them what to do. I suspect anyone wishing to criticize the practice of coasting, would be wiser to quash something really dangerous... like talking on a cell phone while driving. At least the "coasters" are paying attention.

Fuel-economy Maximizing Behavior

Ecomodder.com

This post has been edited by akcaphund: Sep 9 2008, 12:00 PM

yea just leave it in gear... safer, more fuel efficient.

they are also wasting their time thinking it gives any real benefit...

im sure all "coasters" are perfectly safe drivers and never do anything else dangerous in their cars (like talk on the phone) :whistling:

so I am missing something - why is it safer to keep the car in gear going downhill ? I don't put my car in neutral but I'm just curious why this would be considered "unsafe" - it doesn't prohibit braking or anything - LOL

There are folks like yourself (:whistling:), who are intelligent, thoughtful,
and equally scientific in their assessment of the technique who might suggest
otherwise... based on their empirical findings.

Could we have a conversation that is any more Last Week?

Ecomodder.com

This post has been edited by akcaphund: Sep 9 2008, 04:55 PM

thanks.. i was reading the Popular Mechanics article. fact is, the amount you would have to "coast" in order to make it worthwhile makes it more dangerous to everyone else on the roads..

not worth it IMO.. cant see myself getting 1-2 MPG better by doing that, and im already getting 28-30 in my V6, so that's good enough for me...

Sonatas arent meant for phenominal fuel economy... if you want to be more "Eco-Friendly", buy an Accent or Civic or even Elantra... or better yet, a Prius....

do yourself a favor, dont come here and be a prat.. its not becoming... :thumbsup:

This post has been edited by ddix1026: Sep 9 2008, 05:55 PM

Okay, lets say a deer runs into the road and the car in front of you hits it at 70 mph. You will instinctively slam on the brakes and change lanes. However, once you have changed lanes after slowing down to say...40 mph you need to reaccelerate quickly to keep the 18-wheeler behind you from hitting you. But, oh no, you are in neutral and cannot accelerate and in the 1-2 seconds it takes for you to put it in gear the truck is already halfway up your "backdoor".

Many people(not you bab) don't realize how long/far 1-2 seconds is when you are hurtling a 3500lb hunk of metal down the road at 65 mph....

This post has been edited by dcjwlee: Sep 9 2008, 07:01 PM

Along with my Popular Mechanic article, I'd like to add something to remind you folks.

Hyundai's ESC feature works properly when the transmission is connected to the engine to use the engine break.
If you read its manual, it says that ESC works with ABS break and it will lower the gear instantly to activate the engine break.

So if you meet any dangerous situation that requires Hyundai's ESC feature activated while you are coasting in neutral , you may not have a good chance to utilize ESC properly.

Is saving a little gas worthy when it's a matter of saving your life ?

This post has been edited by montclare: Sep 9 2008, 07:37 PM

the fact of all the coaster whiners is that if you are in neutral it will actually take longer to brake in some instances. also taking turns in neutral without the normal engine braking can also enter you into some problems as I learned when I first learned to drive a clutch (thank goodness there was an empty parking lot on the left side of the road).

That being said, rolling down hills or up to red lights (with the foot off the gas) will actually slow you down more than if the car is in neutral. Therefore, you might have to spend extra gas to get back or maintain a normal speed or to to get back up to speed.

I thought rolling in neutral is like being towed. You never tow an auto if the power wheels are rotating. You are essentially rotating the torque converter output and this will overheat and damage the unit. I was always told to be in gear when the car is moving. If you drift in neutral for long enough you will damage the torque converter, and I believe the distance required is not that great.

This post has been edited by nickpike: Sep 12 2008, 09:00 PM

(QUOTE: From Popular Mechanic magazine :

Most fuel-injected cars turn the fuel delivery completely off when you lift your foot from the accelerator.)


Theres a major problem with this statement. My foot is not on the accelerator when I'm stopped for a red lite, So how does the engine keep running with no gas?