Ignition vs. Roll start?

[Alypuppy]

I must say I am impressed that with the Yaris mileage obtaining 40mpg over 1368 miles with a good mix of long freeway driving through New York and Massachusetts on winter fuel and tires. I cannot wait for summer!

However, I have a question. There are a lot of hills in my area and I often find places to cost for over a quarter of a mile. For these I turn of the car and let it roll and am even able to roll into and park my car in the school parking lot after .2 miles of costing and over 360 degrees of turning.

Most of my coasting, though, is when I see a red light in the distance. Sometimes the light turns green and I love the extra mpg boost from not having to start from a full stop, but I would like to know:

--> Which is better? Roll start the car in an appropriate gear? Or use the ignition system to start the car? Also, many say the wear and tear of ignition is similar to 7 seconds of the engine being on, so I turn my car off for nearly every light and am debating about turning off the car to roll up to stop signs... is there too much of a good thing? I do use the fuel shutoff DFCO (sp) as well, but I find I would rather just turn the car off and coast for greater distances.

Also, did I notice that the ODO only counts when the car is actually in the on position? After driving an SUV, the lack of power steering in the Yaris feels like the power steering in my Xterra, and it seems the break hydraulics only repressurize when the engine is on. I cannot afford a Scangauge, but do I have to turn the car back to the on position without igniting the engine to have a more accurate mileage calculation? Plus, it gets a little cranky and likes to turn the engine back on if it has not spun down fully and it is a bit distracting to have to turn the car on and off several times to finally but the engine to sleep.
Is this true for the other hypermilers? It's funny, sometimes I feel like my car is off more than it is on!


Thank you
Alypuppy

09 HB Manual Trans.

[BailOut]

I must say I am impressed that with the Yaris mileage obtaining 40mpg over 1368 miles with a good mix of long freeway driving through New York and Massachusetts on winter fuel and tires. I cannot wait for summer!

However, I have a question. There are a lot of hills in my area and I often find places to cost for over a quarter of a mile. For these I turn of the car and let it roll and am even able to roll into and park my car in the school parking lot after .2 miles of costing and over 360 degrees of turning.

Most of my coasting, though, is when I see a red light in the distance. Sometimes the light turns green and I love the extra mpg boost from not having to start from a full stop, but I would like to know:

--> Which is better? Roll start the car in an appropriate gear? Or use the ignition system to start the car? Also, many say the wear and tear of ignition is similar to 7 seconds of the engine being on, so I turn my car off for nearly every light and am debating about turning off the car to roll up to stop signs... is there too much of a good thing? I do use the fuel shutoff DFCO (sp) as well, but I find I would rather just turn the car off and coast for greater distances.

Also, did I notice that the ODO only counts when the car is actually in the on position? After driving an SUV, the lack of power steering in the Yaris feels like the power steering in my Xterra, and it seems the break hydraulics only repressurize when the engine is on. I cannot afford a Scangauge, but do I have to turn the car back to the on position without igniting the engine to have a more accurate mileage calculation? Plus, it gets a little cranky and likes to turn the engine back on if it has not spun down fully and it is a bit distracting to have to turn the car on and off several times to finally but the engine to sleep.
Is this true for the other hypermilers? It's funny, sometimes I feel like my car is off more than it is on!


Thank you
Alypuppy

09 HB Manual Trans.

Hello Alypuppy,

It sounds like you're off to a great start with hypermiling! :clap:

When you are moving at anything faster than 10 MPH and want to restart, bump start in 5th and then quickly shift to the appropriate gear and go. I do this several times per day.

Correct, the odometer only increments when the ignition switch is in the "On" position. This is also the necessary switch position for the electric power steering assist.

Yes, the difficulty with turning the engine off is normal in this car. I'm not sure why but I think it is due to the fuel that is queued up on the rail when we stop the engine at higher RPM. My trick is to cycle the ignition switch to the "Off" position, count to two-one-thousand, then cycle it back to the "On" position.

[Alypuppy]

Thank you Brian! =o)

[sbergman27]

Just drive normally. The Yaris is smart enough to cut the fuel completely when:

1. The accelerator pedal is at idle position.
2. The transmission is in gear.
3. The clutch is engaged.
4. Engine speed is above 1100 rpm. (I think it's 1100 anyway.)
5. Engine is at normal operating temperature.

Your fuel consumption will be zero under those conditions. Not even the normal 0.2 GPH for idling will be used. Search for "DFCO", or "Deceleration Fuel Cut Off".

-Steve

[1stToyota]

I must say I am impressed that with the Yaris mileage obtaining 40mpg over 1368 miles with a good mix of long freeway driving through New York and Massachusetts on winter fuel and tires. I cannot wait for summer!

However, I have a question. There are a lot of hills in my area and I often find places to cost for over a quarter of a mile. For these I turn of the car and let it roll and am even able to roll into and park my car in the school parking lot after .2 miles of costing and over 360 degrees of turning.

Most of my coasting, though, is when I see a red light in the distance. Sometimes the light turns green and I love the extra mpg boost from not having to start from a full stop, but I would like to know:

--> Which is better? Roll start the car in an appropriate gear? Or use the ignition system to start the car? Also, many say the wear and tear of ignition is similar to 7 seconds of the engine being on, so I turn my car off for nearly every light and am debating about turning off the car to roll up to stop signs... is there too much of a good thing? I do use the fuel shutoff DFCO (sp) as well, but I find I would rather just turn the car off and coast for greater distances.

Also, did I notice that the ODO only counts when the car is actually in the on position? After driving an SUV, the lack of power steering in the Yaris feels like the power steering in my Xterra, and it seems the break hydraulics only repressurize when the engine is on. I cannot afford a Scangauge, but do I have to turn the car back to the on position without igniting the engine to have a more accurate mileage calculation? Plus, it gets a little cranky and likes to turn the engine back on if it has not spun down fully and it is a bit distracting to have to turn the car on and off several times to finally but the engine to sleep.
Is this true for the other hypermilers? It's funny, sometimes I feel like my car is off more than it is on!


Thank you
Alypuppy

09 HB Manual Trans.

Just drive normally. The Yaris is smart enough to cut the fuel completely when:

1. The accelerator pedal is at idle position.
2. The transmission is in gear.
3. The clutch is engaged.
4. Engine speed is above 1100 rpm. (I think it's 1100 anyway.)
5. Engine is at normal operating temperature.

Your fuel consumption will be zero under those conditions. Not even the normal 0.2 GPH for idling will be used. Search for "DFCO", or "Deceleration Fuel Cut Off".

-Steve

+1

Yes, just drive normally, and let the car do its job...no need for the added distraction

[BailOut]

+1

Yes, just drive normally, and let the car do its job...no need for the added distraction
I wholeheartedly disagree. The car only knows how to do its job one way, and that's the way the engineers thought it out. Their way is by far not the only way.

And cycling the ignition is not a "distraction". Your eyes don't leave the road, you still have assisted steering, and the brakes are good for 4-5 touches. Seriously, of all the things that one can gripe on for being a distraction while driving, cycling the ignition is at the bottom of my list.

There is a time and place for DFCO usage but it has two severe limitations:

1) It steals momentum.
2) The engine uses fuel again once any of its conditions are no longer met.

Coasting with the engine off is much more efficient in all aspects when you know you'll be coming to a stop for a while, or when you want to maintain more momentum in between the times you let the engine run.

[fmicle]

The only concern that I have about roll starting the car is based on an article that I read a few years back. There is a risk for unburnt fuel to end up in the catalytic converter, where, together with a spark from the engine (since the first cat is quite close to the exhaust header) could cause a burn (mini-explosion) inside the cat. That would most likely destroy it.

Having said that, I've roll-started the Yaris a few times before and everything was fine, but I don't think I'll ever try to roll-start it when the engine is cold.

Back home in Romania, when I was a kid, my dad had a crappy car and I remember the countless times we would push it down the street for half a block to start it. But that was an older car with a carburetor engine.

Since most people have automatic transmissions here in the US, I always wondered, is it possible to roll start an AT car? I remember my Jeep Cherokee had a low gear (1), the only setting that would give me engine brake, but I've never tried to roll start it... I was afraid of breaking it :smile:

[Yaris Hilton]

No, you can't roll start an automatic.

[1stToyota]

I must say I am impressed that with the Yaris mileage obtaining 40mpg over 1368 miles with a good mix of long freeway driving through New York and Massachusetts on winter fuel and tires. I cannot wait for summer!

However, I have a question. There are a lot of hills in my area and I often find places to cost for over a quarter of a mile. For these I turn of the car and let it roll and am even able to roll into and park my car in the school parking lot after .2 miles of costing and over 360 degrees of turning.

Most of my coasting, though, is when I see a red light in the distance. Sometimes the light turns green and I love the extra mpg boost from not having to start from a full stop, but I would like to know:

--> Which is better? Roll start the car in an appropriate gear? Or use the ignition system to start the car? Also, many say the wear and tear of ignition is similar to 7 seconds of the engine being on, so I turn my car off for nearly every light and am debating about turning off the car to roll up to stop signs... is there too much of a good thing? I do use the fuel shutoff DFCO (sp) as well, but I find I would rather just turn the car off and coast for greater distances.

Also, did I notice that the ODO only counts when the car is actually in the on position? After driving an SUV, the lack of power steering in the Yaris feels like the power steering in my Xterra, and it seems the break hydraulics only repressurize when the engine is on. I cannot afford a Scangauge, but do I have to turn the car back to the on position without igniting the engine to have a more accurate mileage calculation? Plus, it gets a little cranky and likes to turn the engine back on if it has not spun down fully and it is a bit distracting to have to turn the car on and off several times to finally but the engine to sleep.
Is this true for the other hypermilers? It's funny, sometimes I feel like my car is off more than it is on!


Thank you
Alypuppy

09 HB Manual Trans.

I wholeheartedly disagree. The car only knows how to do its job one way, and that's the way the engineers thought it out. Their way is by far not the only way.

And cycling the ignition is not a "distraction". Your eyes don't leave the road, you still have assisted steering, and the brakes are good for 4-5 touches. Seriously, of all the things that one can gripe on for being a distraction while driving, cycling the ignition is at the bottom of my list.

There is a time and place for DFCO usage but it has two severe limitations:

1) It steals momentum.
2) The engine uses fuel again once any of its conditions are no longer met.

Coasting with the engine off is much more efficient in all aspects when you know you'll be coming to a stop for a while, or when you want to maintain more momentum in between the times you let the engine run.

Maybe not to you, but it is for the OP. If you're quoting me, it's because I was quoting the OP. I wouldn't know, I'd never be silly enough to kill my engine while driving. :rolleyes:

[sbergman27]

I wouldn't know, I'd never be silly enough to kill my engine while driving. :rolleyes:
It seems that some hypermilers don't care that much about safety, steering, or braking except insofar as particular techniques involving them might yield a half a percent increase in their MPG figures:

http://tinyurl.com/yg2e4kz

And honestly, to someone who's other car regularly gets in the 50-60 mpg range when driven normally... it seems a little silly to me to see Yaris drivers going to such lengths to go from forty-something to forty-something-point-one.

-Steve

[Tamago]

save gas while slamming into the car in front of you when you have no power brakes?

yeah that sounds like a hypermiler.

[sbergman27]

save gas while slamming into the car in front of you when you have no power brakes? yeah that sounds like a hypermiler.
Momentum would be conserved.* So while the collision would hurt your fuel economy slightly, the guy you rear end should see a slightly better number on his next fill up.

-Steve

* Minus a little energy lost to heat during the collision itself.

[Tamago]

Momentum would be conserved.* So while the collision would hurt your fuel economy slightly, the guy you rear end should see a slightly better number on his next fill up.

-Steve

* Minus a little energy lost to heat during the collision itself.

i am literally rolling on the floor laughing. thank you for your perfect explanation of "conservation of energy" law.

[Bluevitz-rs]

No, you can't roll start an automatic.

That's not entirely true. The old 2 speed powerglide transmissions have a transmission pump on the output shaft making it possible to build enough pressure inside to spin the engine. Though I think you'd need to get it going about 20-30km/h before that would happen.

But as for the regular Auto tranny, not a chance in anything. In fact, you most you can't even flat tow because the bearings inside the transmission don't have any pressurized lubrication due to the fact that the pump is located on the input shaft. So without the engine turning you have no oil circulation and could end up with fried bearings.

PS, that goes for you hypermilers out there with autos. Shut your engine off at your own risk of doing costly internal damage while trying to save a few pennies of fuel.

[BailOut]

save gas while slamming into the car in front of you when you have no power brakes?

yeah that sounds like a hypermiler.
You seemed to have missed the point that the brakes are still good for 4-5 touches before the vacuum needs to be recharged. I would also like to point out that in well over 3mil miles of hypermilers on the road, not a single hypermiling-related accident has been reported by drivers nor by any police force anywhere in the world.

I understand that hypermiling is different than what you know, but please do not sensationalize it. It is simply a different way to drive a car, and it works.

[sbergman27]

You seemed to have missed the point that the brakes are still good for 4-5 touches before the vacuum needs to be recharged.
And then there's steering... and added distraction... and delay in getting the engine going and the transmission back in gear should you unexpectedly need it. The list goes on...

I would also like to point out that in well over 3mil miles of hypermilers on the road, not a single hypermiling-related accident has been reported by drivers nor by any police force anywhere in the world.
You cannot possibly make that claim with any certainty. And it's very likely not true. I'd like to see some concrete evidence in support of that claim.

I understand that hypermiling is different than what you know, but please do not sensationalize it. It is simply a different way to drive a car, and it works.
Unsafe driving practices are unsafe driving practices. No matter how you want to want to gloss over them. Pointing out the added danger incurred by the hypermilers, and others who have to share the roads with them, is not, by any means, "sensationalizing" the matter.

There are reasonable fuel saving practices... which are, in general, good for safety, as well. And then there are foolish practices which annoy and endanger the hypermiler and others. Fortunately, the reasonable, safe, and non-annoying ones also yield the bulk of the actual FE benefits.

-Steve

[Tamago]

You seemed to have missed the point that the brakes are still good for 4-5 touches before the vacuum needs to be recharged. 4-5 touches, but in that panic moment when you NEED the vacuum, where is it? .8 miles back when you getting a boner over saving 3oz of fuel..... I would also like to point out that in well over 3mil miles of hypermilers on the road, not a single hypermiling-related accident has been reported by drivers nor by any police force anywhere in the world. so you think a hypermiler is going to report that his/her own stupid actions caused him to rear-end the guy in front of him? "yes officer, well, i turned off my engine, to save fuel, and somehow it rear-ended the guy in front of me in the process".. yeah right... he/she told the cop that the "throttle stuck" and he was forced to slam into the guy in front..... wait, that sounds VERY familiar.

I understand that hypermiling is different than what you know,

i perfectly understand the obsession with "saving 3mpg".. it's much like collecting baseball cards or "action figures" hoping that in 30 years they'll be worth something.. but please do not sensationalize it. there's nothing sensational about wasting time to save pennies It is simply a compromise for time over distance.. a different way to drive a car, and it works.[/QUOTE]

you do what you gotta do... but congratulating a guy about his ability to coast down a hill sans-power-braking is just retarded. it's not worth the ounces of fuel saved... especially considering the fact that most of you are wasting the money spent on gas...... on some other stupid obsession, like action figure collections...

[sbergman27]

it's not worth the ounces of fuel saved...
One thing that generally gets lost in these discussions is the true motivation. It's not the pennies worth of fuel saved. It's being able to go on forums like these and say "I finally hit 50 mpg!" and have a couple dozen people 'attaboy you for doing so well. That's the true motivation and potential pay off.

-Steve

[BailOut]

One thing that generally gets lost in these discussions is the true motivation. It's not the pennies worth of fuel saved. It's being able to go on forums like these and say "I finally hit 50 mpg!" and have a couple dozen people 'attaboy you for doing so well. That's the true motivation and potential pay off.

-Steve
That's quite an assumption on your part, and an incorrect one at that.

I'm beginning to sense a pattern here...

[sbergman27]

That's quite an assumption on your part
If you are arguing that a general sense of "I'm being green" is often involved, I would agree. But by the time one gets to things like coasting with the engine off, the game has become more about the numbers than about the green.

-Steve

[Loren]

especially considering the fact that most of you are wasting the money spent on gas...
I waste the money I save by hypermiling (which, honestly, is NOT very much... I added it up to maybe $150/year max) on motorsports entry fees!

I don't get extreme with it. I don't drive slower than the flow of traffic, and generally don't accelerate slower than they typical "slow poke", I don't run red lights, and... what was this thread about? Oh yeah... I don't shut off the ignition in my normal driving. To me, it's far more trouble than it's worth for daily driving.

As with many things, there are different levels of "hypermiling". Don't assume that everyone who does it is the extreme example. I do it merely to entertain and challenge myself in some way other than pushing the limits of the car's acceleration and handling ability on the street. Keeps me out of trouble.

[BailOut]

If you are arguing that a general sense of "I'm being green" is often involved, I would agree. But by the time one gets to things like coasting with the engine off, the game has become more about the numbers than about the green.

-Steve
That's quite an assumption on your part, and an incorrect one at that.

I DO sense a pattern here...

[Gideon]

I'm assuming you can't think of a good response to sbergman or tamago, so you're just babbling about assumptions now.

lol, well judging from your reply and join date I'm going to assume you're quite new and don't know BailOut very well. :rolleyes:

My guess is he wants to conserve energy by not having to type out a multi-paragraph reply justifying his passion for conserving finite resources. :laugh:

[1stToyota]

One thing that generally gets lost in these discussions is the true motivation. It's not the pennies worth of fuel saved. It's being able to go on forums like these and say "I finally hit 50 mpg!" and have a couple dozen people 'attaboy you for doing so well. That's the true motivation and potential pay off.

-Steve

You're wrong, it IS about the pennies, or at least it is with the guy you're debating. Not too long ago he worked it out that if someone is able to avoid using one's blower motor for 75 years!! they'll save enough $$ to get 2 free tanks of fuel in their Yaris. WOW! I doubt that anybody has ever done that or will ever do that so I guess we'll trust his math.

I don't know, I drive with the flow of traffic, run 32 psi in my tires, leave my engine running when going down hills, use my accessories, ignore my gas gauge until it's time for a refill and still manage to get between 41-44 mpg...probably close to the average hypermiler w/ their mpg banners in their sigs, at this forum.

[1stToyota]

You seemed to have missed the point that the brakes are still good for 4-5 touches before the vacuum needs to be recharged.

I'm sorry, but a guy going down hill w/ the motor shut off, counting how many safe touches are left in his brakes is like a guy playing Russian roulette bragging that he's still got 5 empty chambers. :wink:

[Rick]

Nope, It's more like someone in a gunfight with a revolver. While he only has six shots before he has to reload (bump-start the engine), if he can't solve his immediate problem in six shots he really shouldn't be attending gunfights (shouldn't be driving).

[1stToyota]

And just hope that one of your shots isn't a misfire; might just be the last thing you remember.

[Loren]

You guys know that you don't lose all braking just because you run out of vacuum assist, right?

The Yaris has a pretty small amount of vacuum reserve, I've run out of assist on the race track a few times and near the end of autocross courses often. It's scary when you're not expecting it, but if you recognize what's happening, it's not a big deal. Just press harder on the brake pedal, the brakes still work.

(One of these days I'm going to experiment with removing the vacuum altogether just to see if the consistency of feel is more acceptable to me than the assist cutting out unexpectedly.)

[1stToyota]

And I hope that you also realize that if you lose your power assist you're brakes aren't nearly as effective. By the time you figure out that you've lost the assist and you'll have to press a lot harder it could be too late. Oh well.

And you lost vacuum to your booster at the track, or are you experiencing brake fade from overuse?

[Loren]

And you lost vacuum to your booster at the track, or are you experiencing brake fade from overuse?
I've had both. At autocrosses, the brakes never get hot enough to pad fade (with upgraded pads... the stock pads would fade regularly) or boil fluid. I left-foot-brake when I autocross, so I'm on and off the brakes a lot more than most people. Sometimes near the end of a run, I'll run out of boost. Last weekend, it was happening at exactly the same place on every run. Just one of those things.

Pad fade used to happen at the track a lot until I installed brake cooling ducts.

[Boost Addicted]

On the matter of shutting off your ignition while rolling...I just thought I'd mention that in addition to the stupidity and danger of the act, it's also illegal. And as someone mentioned, when you're in gear, and your foot's off the gas, you're using zero fuel... The injectors turn off, and your wheels keep the engine turning.

[BailOut]

On the matter of speeding...I just thought I'd mention that in addition to the stupidity and danger of the act, it's also illegal.
There. Fixed it for ya.

[yaris2010RS]

wow.....lol, y do touchy subjects always turn into bit@h fits?

lol, i have somewhat the same question as the OP, whats better for the car, puch start or crank? jsut about everywhere i park, i am capable of rollstarting it (and i dont know if anyone has tried it, but out little yaris, hb atleast, is so light u can push start it yourself, lo0l, me and my friends got a good kick out of it) so what is better in the long run (no one really cars about MPG, jsut for the car itself)

and really, this car is so great on gas. i only get a +-30km difference between tanks and thats one tank of WOT (no my car isn't involved in the recall..... i'm jsut a teen) to nbormal driving. i'm so hapy with it

[ddongbap]

save gas while slamming into the car in front of you when you have no power brakes?

yeah that sounds like a hypermiler.

I LOL"d so hard after reading this.

[Bluevitz-rs]

Roll starting a manual is no different than down shifting. Put it in 1st or 2nd and let the clutch out, don't touch the throttle and the car starts. No electrical energy required.

Plus for the hypermilers out there, you're saving gas because you don't have to regenerate the energy lost in the battery from using the starter. :eyebulge:

[1stToyota]

On the matter of shutting off your ignition while rolling...I just thought I'd mention that in addition to the stupidity and danger of the act, it's also illegal. And as someone mentioned, when you're in gear, and your foot's off the gas, you're using zero fuel... The injectors turn off, and your wheels keep the engine turning.

+1 :smile:

[1stToyota]

Roll starting a manual is no different than down shifting. Put it in 1st or 2nd and let the clutch out, don't touch the throttle and the car starts. No electrical energy required.

Plus for the hypermilers out there, you're saving gas because you don't have to regenerate the energy lost in the battery from using the starter. :eyebulge:

Unless they're the sort that shuts off their motor at every traffic light that detains them for more than 7 seconds, or whatever the magic number of seconds it was that they've equated to save that .002 cents...at the risk of getting to buy a starter and battery a little bit sooner. :rolleyes:

[BailOut]

Unless they're the sort that shuts off their motor at every traffic light that detains them for more than 7 seconds, or whatever the magic number of seconds it was that they've equated to save that .002 cents...at the risk of getting to buy a starter and battery a little bit sooner. :rolleyes:
I'm coming up on 60k miles with the OEM battery and starter despite using them several times per day. What is the magic number that they should blow up at, do you think? Tell us, oh doomsayer! :bellyroll:

[1stToyota]

I'm coming up on 60k miles with the OEM battery and starter despite using them several times per day. What is the magic number that they should blow up at, do you think? Tell us, oh doomsayer! :bellyroll:

Well l'il sugarcoater, please tell us what causes a starter to fail...from usage? I'm sure you're ready to deny and debunk with some more of that 1.5 million miles of recorded and hidden fuzzy math of yours! :tongue:

[Rick]

Engine-off coasting is not always a safe thing to do. It's not always an unsafe thing to do. It's very situational. If you have doubts about it's safety in a give set of circumstances then don't do it. I don't always do it. I generally don't bother in the cold winter months because keeping a hot engine is problematic. I don't bother if DFCO will work, but DFCO isn't an option on the longer coasts because it scrubs off too much momentum. On the longer coasts if the situation allows (I.E. nothing at all to potentially interact with) I pop it into neutral, key back one click until the engine spins down, and then key on again. When the coasting is over with I just put it back in the proper gear for the vehicle speed, release the clutch and drive on. No drama whatsoever. Some passengers haven't even noticed when it was done. (they weren't sleeping)

The law prohibiting it, if there is one where you are, is rooted in the bad old days when cars were less agile and much much less reliable than they are now. It's not so relevant any more. Heck, until very recently it was illegal in St Paul, MN for anyone but Police and Fire to have red vehicles. Just an old, old law that no one bothered to enforce or repeal.
According to a friend in law enforcement, short of a confession or an eyewitness testimony from a passenger, you could never get a conviction for that anyhow.

On wearing out the starter:

I'm not sure that obsessive killing and restarting of the engine with current starter technology is cost effective in the long run but I'm not going to crap on someone who chooses to find out. How will we ever have any data on that if no one tries it?

[sbergman27]

Engine-off coasting is not always a safe thing to do. It's not always an unsafe thing to do.
What about that time that it seemed safe, but suddenly something totally unexpected happened and it wasn't, and you and your family were killed in the terrible accident that resulted?

Safety isn't about what you expect. It's about what you don't and can't expect. And it only takes once. Think about it.

World energy usage, from fossil fuels, is about 400 exajoules per year. That's equivalent to about 3.2 trillion gallons of gasoline per year. About 100,000 gallons per second. The Yaris uses about 1/30th of a teaspoon of gasoline per second at idle. About 2 thousandths of a millionth of the average world rate of consumption. And, of course, the difference between coasting in 'D' and coasting with the engine off is effectively a fraction of that 1/30th of a teaspoon. Just the difference from engine braking. You can tap the accelerator from time to time to maintain speed, remaining in DFCO most of the time. I'm going to guess that the difference comes out to be about 1/300th of a teaspoon per second. (This assumes that engine braking is costing you about 10%. Works out to about a 3 mph/sec deceleration with your foot off the pedal. Season to taste.) Is it really worth it to save 1/300th of a teaspoon per second? 1/4000th of a gallon per minute?

-Steve

[BailOut]

Is it really worth it to save 1/300th of a teaspoon per second? 1/4000th of a gallon per minute?
Oil extraction, processing, transportation, refinement and usage are all ecological disasters of an epic scale, and the human fallout from all of it (oppression, war, displacement, etc.) is absolutely catastrophic.

The less each of us uses of it, and the more responsibly each of us uses it, the less the world will need each day. The less the world needs each day the less pressure there is on the whole human and ecological systems.

The way I see it each of us is either part of the problem or part of the solution, and by reducing my demand for oil I feel that I am not part of the problem.

All the scaremongering and fuzzy math (the output of an equation is only as good as the input, and you continually miss a huge chunk of the input) in the world changes none of this.

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We know that some of you don't care for hypermiling but, frankly, I am getting sick and tired of the scare tactics and gloom and doom coming out each and every time anyone posts anything about a hypermiling technique.

You don't see us FE types parading into the Performance forum and bashing speeding or track days or spending huge amounts of money for minuscule gains. You don't see us pestering the Cosmetic forum about the things we think are silly, or making fun of how much money is spent on those types of things.

We expect the same in return here in the Fuel Economy forum. If you have nothing positive to contribute to a thread then please spend your time elsewhere. If you can't stomach conversations about hypermiling then please spend your time elsewhere.

This is indeed the Fuel Economy forum,and hypermiling is a large part of that. Please get over it or move on.

[yarrr]

You don't see us FE types parading into the Performance forum and bashing speeding or track days or spending huge amounts of money for minuscule gains. You don't see us pestering the Cosmetic forum about the things we think are silly, or making fun of how much money is spent on those types of things.

We expect the same in return here in the Fuel Economy forum. If you have nothing positive to contribute to a thread then please spend your time elsewhere. If you can't stomach conversations about hypermiling then please spend your time elsewhere.

Sorry to butt in, but -

People DO bash speeding threads. Going to the track and modding your car is safe and legal, but if you feel the need to bash, go ahead. Turning your vehicle off is not safe, and not legal in most states as has been pointed out. It seems the only person in this thread that "can't stomach" the conversation is you, as everyone else is staying on topic and bringing up valid points which you choose to ignore.

[tomato]

OK, let's everybody take a deep breath, in fact, I'm gonna lock this thread temporarily while you all cool off.

Let's see what happens in a couple of hours, OK? Thanks.

[jhsouders]

And then there's steering... and added distraction... and delay in getting the engine going and the transmission back in gear should you unexpectedly need it. The list goes on...


You cannot possibly make that claim with any certainty. And it's very likely not true. I'd like to see some concrete evidence in support of that claim.


Unsafe driving practices are unsafe driving practices. No matter how you want to want to gloss over them. Pointing out the added danger incurred by the hypermilers, and others who have to share the roads with them, is not, by any means, "sensationalizing" the matter.

There are reasonable fuel saving practices... which are, in general, good for safety, as well. And then there are foolish practices which annoy and endanger the hypermiler and others. Fortunately, the reasonable, safe, and non-annoying ones also yield the bulk of the actual FE benefits.

-Steve


Wow Steve, No evidence is required to state that no accidents have been caused by hypermilers, there is plenty of evidence to show of other driving methods causing accidents... aka drunk driving, falling asleep at the wheel, driving aggressively. But driving passively, or hypermiling is not one of them.

Hypermiling is much safer than the other driving methods i have previously stated, why are you ragging on it so much huh?

Hypermiling is all about the getting the most MPG out of your car without jeopardizing safety, we are not trying to get ourselves killed.

[yarrr]

there is plenty of evidence to show of other driving methods causing accidents... aka drunk driving, falling asleep at the wheel, driving aggressively. But driving passively, or hypermiling is not one of them.

That's because there's no blood/breath test for smugness.

I like the fact we're still ignoring the fact that turning your engine off in motion is illegal in most states.

[jhsouders]

That's because there's no blood/breath test for smugness.

I like the fact we're still ignoring the fact that turning your engine off in motion is illegal in most states.


It may be illegal, but there is no way to prove that turning off your engine is indeed dangerous when you know what you're doing. Power steering doesn't matter at highway speeds, and you have about 5 pumps on the breaks before you lose those, on the highway you hardly ever use breaks anyway. For all the electronics, blinkers, and such, just turn your key back to the on position and you have it.

There really is no evidence that its dangerous to do so, or even any way for them to catch us in the act. As one person said, we can do it with passengers and they don't even notice it.

[fmicle]

That's because there's no blood/breath test for smugness.

I like the fact we're still ignoring the fact that turning your engine off in motion is illegal in most states.

Does that make a hybrid illegal? :iono:

[Canuck]

Does that make a hybrid illegal? :iono:

When tha gas engine goes off, full power is still applied by the electric. It's the shutting off of all power sources while in motion that is illegal.

[dingbat]

Interesting thread. Got me thinking about some things.

What does the extra wear an tear on the car translate to in barrels of crude? If the life of the starter, trany, etc. is shortened, how much energy does it take to manufacture, transport, and install those parts? Is it less than the amount saved by this practice and how much less?

If shutting the engine off when coasting does increase the risk of accident, what is the percentage of people doing this that will end up in an accident? Will the gas savings of all the other folks who don't end up in an accident off-set the equivalent cost in crude of the tow truck, police cruiser, medical emergency vehicle, being run to and from the scene for the one that does? The cost of replacement parts, installation of those parts etc......?

[dingbat]

Nope, It's more like someone in a gunfight with a revolver. While he only has six shots before he has to reload (bump-start the engine), if he can't solve his immediate problem in six shots he really shouldn't be attending gunfights (shouldn't be driving).

Poor analogy.
Never underestimate a man with a wheel gun. (http://www.youtube.com/watch?v=cY9CyA9s41c):eyebulge::bow:


With a little practice and a speed loader, even a mere mortal can put a revolver back in play fairly quickly.

[127.0.0.1]

I'm coming up on 60k miles with the OEM battery and starter despite using them several times per day. What is the magic number that they should blow up at, do you think? Tell us, oh doomsayer! :bellyroll:



real info on starters and how long they last.

it is how long the copper contacts last.

which is usually around 110,000-160,000 miles on a long-trip dd
and 70,000 - 100,000 miles on a short trip dd
---------------------------------------
replacing the contacts (which are 20 bucks) the starter
should last past 350,000 miles.

[Bluevitz-rs]

real info on starters and how long they last.

it is how long the copper contacts last.

which is usually around 110,000-160,000 miles on a long-trip dd
and 70,000 - 100,000 miles on a short trip dd
---------------------------------------
replacing the contacts (which are 20 bucks) the starter
should last past 350,000 miles.

And if you own a torch and a brass rod, you can braze the worn part, fill it down and it'll outlast the life of the engine.


The starter contacts died on my old '85 Honda when it only had 60 something thousand Km on it. My dad brazed the contacts, and it now has 348000km on it. I don't know why they don't just make them out'a brass to begin with? Oh, wait, they'd never need to sell you a new $300 starter.

[yarrr]

Interesting thread. Got me thinking about some things.

What does the extra wear an tear on the car translate to in barrels of crude? If the life of the starter, trany, etc. is shortened, how much energy does it take to manufacture, transport, and install those parts? Is it less than the amount saved by this practice and how much less?

If shutting the engine off when coasting does increase the risk of accident, what is the percentage of people doing this that will end up in an accident? Will the gas savings of all the other folks who don't end up in an accident off-set the equivalent cost in crude of the tow truck, police cruiser, medical emergency vehicle, being run to and from the scene for the one that does? The cost of replacement parts, installation of those parts etc......?

:clap:

:clap:

:clap:

Take out the ifs, and I agree 100%. Don't forget if you're turning your engine off, you're already at 40+ PSI in the tires - combined with no engine, I'm betting bailout&co hit 0 about 20-30 feet after a stock yaris. This is what is called "common sense" and if you use it, you realize just about every hypermiling "technique" has a chance of costing you your life at worst, and more money than you're saving on gas at best.

I don't get extreme with it. I don't drive slower than the flow of traffic, and generally don't accelerate slower than they typical "slow poke", I don't run red lights, and... what was this thread about? Oh yeah... I don't shut off the ignition in my normal driving. To me, it's far more trouble than it's worth for daily driving.

This is safe sane hypermiling. Saving gas, no chance of killing people, nice stuff all around, no?

Much past that, its just a game and a gamble if you are going to save any money.