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Old 05-27-2007, 12:57 AM   #1
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Fuel Efficiency and the Yaris

With today's rising gasoline prices and the growing awareness of the ecological, geopolitical and finite resource issues that come with an oil-based economy, most people are at some stage of awareness regarding a need for higher fuel efficiency. However, most folks do not have a good idea of where to start, or a solid way to sift real information from a sea of greenwashing, snake oils and disinformation campaigns.

Fuel efficiency (hereafter abbreviated as FE) has just as much to do with the way you drive your car as it does with the kind of car you drive. Fortunately, by design the Yaris can achieve high miles per gallon (MPG), so for the most part any change you make to your driving style will make a noticeable impact. Combining these techniques with things that directly affect your car's performance can yield wholly worthwhile results.

As with most things in the transportation world, when it comes to FE there are easy things to do, some things that are not so easy to do, and then some things that are harder to do. We will take a look at all 3 levels of FE efforts before we are done.

Please be aware that these posts will be a work in progress for some time to come and may change without notice. If you re-use any of the information here please link back to this thread (CCL).

Let's start with the “low hanging fruit”, or the easiest things you can do to make a difference, then move on to the higher levels.
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I often carry 2 carpool passengers and mountain bikes
or snowboards/skis over a 4,500 foot elevation difference.
Click the graphic above to see my detailed mileage logs.

Last edited by BailOut; 06-10-2007 at 07:05 PM.
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Old 05-27-2007, 12:58 AM   #2
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Basic FE

Basic FE:

1) Slow down, and never speed. The faster you travel the more the air resists your vehicle, and the more fuel your engine needs to use in order to keep moving forward at the same velocity (speed). There is a marked increase in air resistance above 55 MPH, and a drastic hit above 65 MPH.

2) Accelerate and brake slowly and steadily, avoiding jackrabbit starts and stops. No one ever got a trophy for getting to the next red light first or getting up to highway speed in the first 200m of an on-ramp, and you can't beat the timing of a stop sign. In the Yaris I try to never let my RPM get above 2,000 unless I need to merge quickly, in which case I allow for 2,200. The only time I get higher than that is on the climbing side of my mountain commute, as once you get into 6% and 7% grades it simply requires more fuel to keep moving.

3) Keep your tires inflated to at least the manufacturers recommendation, or as high as the maximum sidewall rating. This decreases rolling resistance.

4) Keep your vehicle properly tuned. A poorly-running engine will almost always burn more fuel. A failing exhaust system can create more back pressure, making the engine work harder. Etc.

5) Use the smallest, lightest vehicle for the job. In other words, don't take the Suburban to the grocery store if you have a passenger car available.

6) Get the junk out of the trunk. This goes for you as well as for the vehicle. The lighter the vehicle is the less fuel it takes to move it.

7) Run all your errands together, starting with the one furthest from your home. This will allow the engine to stay warm the whole time.

8) The shortest route isn't always the best one. Know the traffic and construction conditions.

9) When not in use remove the camper, bike rack, or any other addition that creates drag.

10) Never drive your vehicle hard before it warms up, and never idle it to warm it up. The Yaris offers a low coolant indicator light in the dash panel that let's you know when it is running in its least fuel efficient state. As for idling to warm it up, remember that you're getting exactly ZERO MPG while idling.

11) Never rev the engine. This accomplishes absolutely nothing but extra wear and tear on the engine for no reason, and more fuel burned for no reason.

12) The realities of pumping fuel. The cost of fuel is generally somewhat arbitrary but is statistically higher near the weekend, so try to fuel up in the middle of the week. It is also more expensive around recognized holidays so try to fuel up early or wait the holiday out. Like most other fluids gasoline is more dense when cold, so filling up in the coolest part of the day will net you as much as 1% more fuel for your dollar. Never fill beyond the automatic shut-off as this dumps raw emissions straight into the atmosphere. When automatic shut-off occurs rotate the pump handle 180 degrees (upside down) for a few seconds so that the remaining fuel in the nozzle goes into your tank.

13) "The Myth of Torque", or "Why you don't need 200bhp to pick the kids up and get groceries". One of the most ridiculous things I've ever heard is someone making fun of a Yaris owner for a lack of torque in the vehicle. We do not live on a race track or rally course and we do not get a trophy for getting home 3 seconds earlier than our neighbor. The Yaris climbs mountains, merges onto the highway and carries a proper weight load just fine, so there is no need for more torque than the stock engine and transmission offer.
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I often carry 2 carpool passengers and mountain bikes
or snowboards/skis over a 4,500 foot elevation difference.
Click the graphic above to see my detailed mileage logs.

Last edited by BailOut; 06-10-2007 at 07:08 PM.
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Old 05-27-2007, 12:58 AM   #3
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Intermediate FE

Intermediate FE:

1) Never idle again, or "Never get ZERO MPG again". Not only is the warm-up idle a bad idea but so is any other kind of idling. When you come to a stop light turn off the engine. When you're waiting in the drive through turn off the engine. When you're at a construction stop turn off the engine. When you're waiting for your friend to get out of the store/restaurant/etc. turn off the engine. In past times this might not have been such a hot idea, but with today's technology and manufacturing processes it only takes about 7 seconds of idling to equate to the engine wear and tear and fuel cost of a warm start.

2) Going from "I can't drive 55" to "I never drive over 55". Many of you may be too young to remember this but not too long ago the Federal speed limit for highways in the U.S. was 55 MPH, and had been so for decades. While that may seem awfully slow to you the reality is that everyone always got where they needed to go, road trips and commutes and vacations occurred, and everyone still had plenty of time left for everything else in life. The raising of the Federal limit to 70 MPH has helped save some folks a bit of time and has helped a few late truck shipments make an on-time delivery, but these things have been accomplished at horrendous costs to fuel efficiency and emissions. As mentioned in the Basic list speeds up to 55 MPH generally share the same aerodynamic efficiency but anything above this speed takes a hit. As such limiting yourself to a maximum speed of 55 MPH is logical and easy to achieve.

3) Take advantage of DFCO (Deceleration Fuel Cutoff). Please see this thread for a detailed discussion on DFCO.

4) Route planning based on known obstacles (stop lights, stop signs, hills, heavy traffic, etc.). Always try to select the path of least resistance. If you can get from point A to point B by avoiding a hill climb but having to go through one more traffic light you are much better off taking the traffic light route. If you live in a highly congested area try taking the access roads or parallel avenues instead of staying on the highway itself. If able try to adjust the times of day you commute to take advantage of lower traffic times.

5) Face-out parking & potential parking. Try to make sure that your first movement is always forward by parking face-out wherever possible, even if this means walking further in a parking lot. Increase the benefit of this by parking face-out on a grade so that you can roll for a ways (fuel-free movement) when it's time to leave.

6) Use monitoring tools such as a ScanGauge II. Please see this thread for a detailed discussion on the SG II.

7) Running tire pressures higher than the max sidewall rating. Disclaimer: There are unconfirmed, anecdotal reports of safety issues associated with this. The “perfect pressure” to run your tires at will vary from tire to tire and vehicle to vehicle but for either a Yaris or Prius running the Bridgestone Potenza RE92 tires (Toyota's stock choice for mud and snow (M+S) rated tires) folks across the Net have achieved the best results between 50 and 60 PSI. I run mine at 60.

8) The realities of fuels. This could be a thread of its own but I will summarize a few finer points here. To make a very long story short, with few exceptions using top-tier (name brand) fuels ends up being cheaper due to not only increased fuel economy but also in upper cylinder health by drastically dropping “gunk” and other unwanted build-up. One reason top-tier fuels cost more is because the companies that sell them have gone to tremendous expense in R&D to find ways to achieve the Federally-mandated additives/reformulations without sacrificing the caloric content of the fuel. Off-brands have no such compunction and use the cheapest additives available at refining time without regard to caloric efficiency. I truly do not mean to endorse any oil company but in the interest of saving you time I will say that, after millions of miles of road testing on all kinds of vehicles and in all parts of the world, Shell and Chevron seem to continually come out on top for fuel efficiency and engine health, so much so that they become the best value.

9) The realities of fuel additives. First let me say that anything containing Acetone is bad and some reformulators and upper cylinder lubricants are good. Acetone may cause a temporary boost in FE but does so at tremendous expense to the non-metal components in your engine such as gaskets and hoses. Other additives may or may not help FE and/or your engine and seem to be at the whim of the cosmos, but some worth looking at are Lucas Fuel Treatment and Ethos FR (I haven't tried this one yet).

10) Modifying your vehicle for FE. There are so many mods that can be done for fuel efficiency that this could be another separate topic. Please see an appendix below for some ideas.

11) Switch to synthetic oils. Using synthetic crankcase and gear oils allows the engine, transmission and differential to operate with less friction. Additionally, a TSB advocating a switch to 5W-20 oil has been located.

11) Fuel rebates. Many credit card and gasoline merchants offer rebate/reward programs for gasoline. Without attempting to endorse any particular company I will say that, as of this writing, American Express' Blue Cash card offers the best rebate program with 5% on gasoline, grocery and pharmacy purchases and 1.25% on everything else (once an annual $6,500 qualifying limit is reached), paid annually. Shell's MasterCard offers a good rebate program with 5% back on all Shell and Jiffy Lube purchases and 1% on anything else you use the card for, paid monthly. Neither card has an annual fee nor charges any fees if you never carry a balance. Also as of this writing Chevron's card doesn't even guarantee participation in a rebate program, and Discover's program is a flat 1% with lots of attached fees.
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Share the Road


I often carry 2 carpool passengers and mountain bikes
or snowboards/skis over a 4,500 foot elevation difference.
Click the graphic above to see my detailed mileage logs.

Last edited by BailOut; 05-04-2010 at 11:45 AM.
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Old 05-27-2007, 12:58 AM   #4
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Advanced FE (Hypermiling) - For educational purposes only

Advanced FE (Hypermiling) - For educational purposes only - attempt at your own risk:

FAS: Forced Auto Stop

P&G: Pulse and Glide

DWL: Driving With Load

DWB: Driving Without Brakes

Close-In Draft (Allow me to quickly debunk the myth that drafting makes the front-runner use more fuel. They already burned the fuel to move the air out of the way and you are merely riding along in their turbulent wake.)

Distant Draft

Surf Draft

Ridge Riding

- Grill blocks & engine blankets. A warm engine is a happy engine, and the Yaris' target temperature is 184F. Anything you can do to help maintain that temperature without causing an overheating scenario is a pure benefit. You can block the grill(s) with cardboard (paint it to match if you like), and you can also use things like sectioned water heater blankets to insulate the top and sides of the engine compartment. Please search the Net for more discourse on these things as the subject is diverse. I may post a DIY next Winter.

- Leave Jack at home. Replace your spare tire, jack, etc. with a patch kit and small, 12V air compressor, or even just a cell phone and road service membership. Also look for other ways to drop weight from the vehicle, such as seat removal.

- Advanced aerodynamics. This is yet another topic that could have its own thread, but I'll touch on the salient points here. Every vehicle has a coefficient of drag (Cd), and the lower the Cd the less drag the vehicle creates as it moves trough the air. You can change your Cd with things like body kits, lowered suspension, etc. Some folks take it to the level of creating custom add-on forms, wheel skirts, etc.
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I often carry 2 carpool passengers and mountain bikes
or snowboards/skis over a 4,500 foot elevation difference.
Click the graphic above to see my detailed mileage logs.

Last edited by BailOut; 05-27-2007 at 03:46 AM.
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Old 05-27-2007, 12:59 AM   #5
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FE mod ideas

FE mod ideas

Window tint (Helps you use less a/c.)

Sun shade (Helps you use less a/c.)

Window Deflectors (Lets you keep the windows cracked to let heat out, even in dusty or rainy weather.)

High-flow, renewable air filter (Fits both the 1.5L and 1.8L.)

Solar trickle charger (So the alternator and engine don't have to make up for bled-off electricity.)

DIY PCV catch can (Keeps the gunk out of your throttle body and combustion process.)
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I often carry 2 carpool passengers and mountain bikes
or snowboards/skis over a 4,500 foot elevation difference.
Click the graphic above to see my detailed mileage logs.

Last edited by BailOut; 10-19-2008 at 06:56 AM.
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Old 05-27-2007, 12:59 AM   #6
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Resources

Resources:

Fuel Economy of Gasoline Vehicles (chevron.com)

"Why Don't I get the EPA Mileage?" by Evan Fusco, MD (PDF file - chicagopriusgroup.com)

"Beating the EPA - The Why’s and how to Hypermile" by Wayne Gerdes (cleanmpg.com)

GasSavers.org

CleanMPG.com

U.S. EPA's fuel economy site (fueleconomy.gov)

State Winter Oxygenated Fuel Program Requirements for Attainment or Maintenance (PDF file - epa.gov)
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I often carry 2 carpool passengers and mountain bikes
or snowboards/skis over a 4,500 foot elevation difference.
Click the graphic above to see my detailed mileage logs.

Last edited by BailOut; 10-19-2008 at 06:57 AM.
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Old 05-27-2007, 01:00 AM   #7
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Additional notes & musings

Additional notes & musings:

There is a lot of information here and it may seem overwhelming at first, but there are 2 important things to remember:

1) You don't have to do it all at once.
2) You don't have to do anything that you are uncomfortable with.

The more involved you get the better your FE will become, the lesser your environmental and geopolitical footprints will be, and the lesser your financial burden at the pump. Yet again I stress that all of this is totally voluntary. I encourage you to go as far as you are comfortable with and then re-evaluate.


How can I calculate my mileage?

The next time you fuel up reset your trip meter (part of the odometer). The time you fuel up after that divide how many miles are shown on your trip meter by how much fuel you filled up with, out to 3 decimal places. Don't forget to reset your trip meter before you drive off. If you do not have a trip meter you can track your miles between tanks by subtracting the odometer reading from the reading at the last fueling.

Here is an example: If I traveled 400 miles since my last fueling and I fill up with 9.822 gallons, then 400 / 9.822 = 40.725 MPG.


What kind of FE can you achieve with your Yaris?

As of this writing I am the highest MPG Yaris driver that I am aware of. As such I'll use myself as an example.

Rather than go into every little detail of what I have stacked against me from an FE perspective let me just say that I live and commute in a mountainous area, we get lots of high winds and snowfall, my Yaris has never had straight gasoline in it (my State and the surrounding States are on E10 (at a minimum) year-round), I have little choice as to my commuting hours, I have just one preferable route to work (the next available route is via another city which adds over 45 miles to the round trip), I run on M+S tires year-round, and I must let my wife drive the Yaris for errands (while she takes it easy on the car for my sake she is not a hypermiler).

With that said my best tank as of this writing is 52.538 MPG and my lifetime average for this car so far can be found in my forum signature. The signature also links to my complete Yaris mileage log, starting from the day I bought it.

My goal is to consistently get 50+ MPG.

Other Yaris drivers that are publicly logging their mileage are showing numbers like 48.201, 45.267, 43.421, 42.364, 46.645, and 42.23 MPG for their best tanks.

This shows you that anyone can beat 40 MPG in the Yaris. Yes, this means you, too!
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I often carry 2 carpool passengers and mountain bikes
or snowboards/skis over a 4,500 foot elevation difference.
Click the graphic above to see my detailed mileage logs.

Last edited by BailOut; 09-07-2007 at 07:59 PM. Reason: Updated my best tank MPG
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Old 05-27-2007, 01:00 AM   #8
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Hmm.... wow... what a popular thread
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Old 05-27-2007, 03:43 AM   #9
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Quote:
Originally Posted by Black Yaris View Post
Hmm.... wow... what a popular thread
No matter what, it is an informative and educational thread that most people can learn something from. Just as daily driving can be improved by appliying certain techniques from the race track, it can also be enhanced with some of these techniques.
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Old 05-27-2007, 08:34 AM   #10
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I feel I can add something in regard to the tire pressure issue. I am now on my second set of tires on my '99 Corolla. This set is identical to the set I had previously. These tires are Kumho 795 Touring A/S. For the first set, I maintained the recommened pressure (this is the pressure listed on the driver's door) which is 30 PSI. These tires wore down to the wear bars at 55K miles and I averaged 35 MPG over this period (roughly 90% highway and 10% city driving). When I purchased the second set, the tire guy I purchased them from suggested I run them at 5 PSI over the recommended pressure. He said not only would my mileage improve, but so would treadwear, handling, and road noise. He was right. I now have about 50K miles on these tires and they aren't even close to being worn down to the wear bars. I've also averaged 38 MPG since I've had this set of tires under the same driving conditions. I'm very happy with these results. The only reason I wouldn'r run them at any higher pressure is that it sacrifices too much in the way of ride comfort. I noticed a difference in stiffness just going from 30 to 35 PSI. I can only imagine how rough the ride would be at the max sidewall pressure (which is 44 PSI).

Over-inflating the tires definitely works however, I would take care not to exceed the max pressure listed on the sidewall for safety reasons.
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Old 05-27-2007, 09:43 AM   #11
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Quote:
Originally Posted by BailOut View Post
13) "The Myth of Torque", or "Why you don't need 200bhp to pick the kids up and get groceries". One of the most ridiculous things I've ever heard is someone making fun of a Yaris owner for a lack of torque in the vehicle. We do not live on a race track or rally course and we do not get a trophy for getting home 3 seconds earlier than our neighbor. The Yaris climbs mountains, merges onto the highway and carries a proper weight load just fine, so there is no need for more torque than the stock engine and transmission offer.
Well, in fact this is where it hurts. It's the weak point of the Yaris engine, speaking in terms of fuel efficiency. This is true especially in city driving and explains why many Yaris owners noticed poor gas mileage in such driving conditions. Lack of low end torque means the car is underpowered when starting from a light, therefore one has to depress even more the gas pedal without producing much more power. Fuel consumption is proportional with the gas pedal travel. Therefore the engine takes more gas while not accelerating as needed.

Try this to better understand: while being it the 3d gear, run at 20mph and try to accelerate, one will notice that no matter how far the gas pedal is depressed - thus injecting more gas into the engine - the gas does not start moving faster. To resume it, the engine took more gas, but the car didn't travel correspondingly during this time. In other words this means poor gas mileage.
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Old 05-27-2007, 10:41 AM   #12
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hystria,

I understand what you are saying but I must point out that if you are watching conditions down the road and making proper adjustments earlier you will never find a time where you need to mash the gas pedal like that. Even when you mash the pedal in a scenario like you mentioned it doesn't necessarily mean the Yaris uses a huge gulp of fuel. Using an SG II will show you that your throttle pedal movements are only suggestions as far as the ECU is concerned. It will only put through as much gasoline as you can burn within the emissions parameters it is happy with.

This by no means indicates that you can run the Yaris hard and expect it to not drink more fuel. It's just that you will hit the maximum fuel rate for most scenarios much earlier than the throttle pedal makes you think.

For example, when climbing my commute mountain I often have the same real-time MPG and fuel rate at 30% throttle as I do at 100% throttle because the ECU was already pegging the math at 30% on the grade.

Due to this I have found that when I'm not hill climbing I rarely - and I mean only once every couple of hundred miles - use more than 20% of the throttle pedal's travel.

Additionally, 20 MPH in 3rd gear is definitely outside the Yaris' power band. If that kind of acceleration is truly needed you'll have to eat the fuel hit in 2nd gear instead.
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or snowboards/skis over a 4,500 foot elevation difference.
Click the graphic above to see my detailed mileage logs.
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Old 05-27-2007, 10:51 AM   #13
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Over-inflating the tires definitely works however, I would take care not to exceed the max pressure listed on the sidewall for safety reasons.
It is extreemly dangerous to run your tires at a pressure higher then the manifacture reccomends, you run a high risk of tire seperation, expecially on the highway when tires are being heated up the most
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Old 05-27-2007, 11:49 AM   #14
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We've been over this before, BailOut's posted a warning as well, overinflation of tires is at your own risk, but anywhere between the manufacturer's recommendation (on the door jamb) and the tire manufacturer's limit (embossed on the side of the tire) should not cause any danger.
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Old 05-27-2007, 11:50 AM   #15
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It is extreemly dangerous to run your tires at a pressure higher then the manifacture reccomends, you run a high risk of tire seperation, expecially on the highway when tires are being heated up the most
I assume you're referring to the tire manufactuer?
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Old 05-27-2007, 03:45 PM   #16
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I assume you're referring to the tire manufactuer?
yes
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Old 06-01-2007, 11:05 AM   #17
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Does hypermiling save gas? Probably NOT!

Before you flame me let me explain ....

This past week I decided to try some of the techniques used by hypermilers to achieve their awsome FE. Even before I heard of hypermiling I was already trying to practice some of their techniques and two weeks ago I achieved the best FE to date (6.4L/100km).

What I did differently last week:
1. Slowed down in general, never above speed limit (kept to 100km/hr on highway and tried not to go above 2500 rpm).
2. Accelerate slower than usual (no revs above 1500rpm from full stop)
3. Brake slowly and steadily.
4. shift to neutral when possible (down hills, approaching red lights, and stop signs)
5. Avoided using A/C (even yesterday on way home when temp was 30c)
6. Below 40km/h until warm light goes out.
7. Looked for "face out parking" opportunities.

Observations:
1. By slowing down, accelerating slowly from stops, breaking slowly, and gliding to stops, you create much more space between you and the car ahead of you. This enrages many drivers behind you and they will hyper-rev their own vehicles to pass you. Result: hypermiler saves fuel BUT in order to pass you the other drivers USE MORE FUEL THAN YOU'VE SAVED. Therefore, unless a majority of drivers change their habits, a zero-sum game. Having said that, I will continue to do this but only when practical.

2. Avoiding the use of A/C is just not realistic. If people could do without A/C they would not purchase vehicles with this feature. I for one will try to use it only when the temp is unbearable.

3. Even something as simple as driving below 40km/h before the engine warms up is very difficult. In the morning coming out of my house drivers get visibly annoyed when I stay just below 40 - I'm not even out of my residential neighbourhood yet where the speed limit is 40! From my house the first stop is about 200m. I have observed drivers turning left, accelerating very fast to take a "short cut" just to avoid staying behind me. I then see them one or two cars ahead of me when I join the major street. Result: hypermiler saves fuel BUT in order to pass you the other drivers USE MORE FUEL THAN YOU'VE SAVED. Therefore, unless a majority of drivers change their habits, a zero-sum game.

4. Looking for "face out parking" opportunities probably cost me more fuel than was saved by not backing out of spaces. If you drive even a few metres to look for a "better" spot, you are probably using more total fuel. Better to take the closest space, go in front-first, and take advantage of your momentum.

5. I achieved 6.1L/100km -a savings of 0.3L/100km. That translates to 1.6L or $1.60 for the week! More on this at the conclusion.

Other comments on BailOut's recommendations:

Basic FE:
1) Slow down, and never speed
2) Accelerate and brake slowly and steadily
- see observation #1

3) Keep your tires inflated to at least the manufacturers recommendation, or as high as the maximum sidewall rating
- this one will actually save fuel but there is a limit. There is also a trade-off between fuel and comfort - most people will opt for comfort even if they have the discipline to check tire pressures on a regular basis.

4) Keep your vehicle properly tuned.
5) Use the smallest, lightest vehicle for the job.
6) Get the junk out of the trunk.
7) Run all your errands together,
8) The shortest route isn't always the best one.
9) When not in use remove the camper, bike rack, or any other addition that creates drag.
10) Never drive your vehicle hard before it warms up, and never idle it to warm it up.
11) Never rev the engine
- these do not affect other drivers' behaviour and will save fuel overall but require a major change in behaviour.

12) The realities of pumping fuel.
- good advice to buy fuel in the middle of the week. However, if more people did this the demand/supply equilibrium would shift and middle of the week would result in higher prices. The hypermiler can save on fuel costs but this is a zero-sum game.

13) "The Myth of Torque", or "Why you don't need 200bhp to pick the kids up and get groceries".
- absolutely true. The trade-off here is fuel savings vs. status/image. Many do not care if their high performance/heavy vehicle uses more gas - they wouldn't be caught dead driving an econobox. The reality - even for fuel economizers like myself - is that for a two car family, at least one of the cars will be a people hauling fuel hog. A family needs something like a mini van even though it will only be used for its intended purpose less than 10% of the time. The "soccer mom" will typically drive the majority of the vehicle's mileage by herself. The only way to get around this dilemma would be for people to have "econoboxes" to commute alone, and a stand alone "people hauler" - not economically possible.

Intermediate FE:
1) Never idle again, or "Never get ZERO MPG again".
- This implies turning off the engine. Problem here is that all other drivers EXPECT your car to be running. Therefore, regarless of what this may imply for the durability of your engine, it's not realistic to expect everyone to turn off their engines at stops. The split second it takes you to turn on the engine contributes to an even greater gap between vehicles leading to the scenario described in observation #1.

2) Going from "I can't drive 55" to "I never drive over 55".
- see observation #1 above

3) Take advantage of DFCO
- this only works best on manual transmissions - most cars are auto. Manual vs auto is a fuel economy vs convenience issue - convenience will always win!

4) Route planning based on known obstacles
- good advice!

5) Face-out parking & potential parking
- see observation #4

6) Use monitoring tools
- good advice here. However, a Scangauge costs about $160. Where I'm writting it would take saving about 160 litres of fuel to make up that expense. I can't see this saving you more than an additional 0.2L/100km. It would take 80,000Kms to break-even. Even though the financial cost/benefit is questionable I will probably end up getting one - we do live in a gadget econmy after all

7) Running tire pressures higher than the max sidewall rating.
- it may be "safe" but NOT PRACTICAL! who wants to drive around on 4 bricks?

8) The realities of fuels
9) The realities of fuel additives.
- ok

10) Modifying your vehicle for FE.
- cost of modifications will probably outweigh fuel savings.

11) Switch to synthetic oils.
- I've done this and it probably works to save fuel. However, if one stays on the same change schedule, the higher cost of the oil may outweigh the fuel savings. For this to lead to actual savings one needs to go beyond the 8000km between oil changes recommended by Toyota.

11) Fuel rebates.
- no savings here since it would require people to switch from other incentives for their current credit cards. For example, for me to take advantage of the rebates given by the oil companies around here (usually less than 1% equivalent) I would have to give up the 1% grocery rebate I get from my current mastercard.

Advanced FE
FAS
- by my understanding this requires turning off the engine - while it saves fuel - IS NOT PRACTICAL!
I don't care how much fuel it saves, my engine WILL NEVER BE OFF WHILE MY CAR IS MOVING! and I'm nearly as obsessive compulsive as the typical hypermiler! No one - but a small handful of individuals - will EVER go for this one.

P&G
DWL
DWB
- by my understanding these techiniques work only for hybrids - a tiny fraction of the vehicles on the road. Current technology makes the financials of owning a hybrid a losing proposition. The higher up-front cost, and the likely higher future maintenance costs (battery replacement for example) of buying a hybrid will not be recouped by savings in fuel.


Drafting
- very dangerous for the typical unskilled driver!

- Grill blocks & engine blankets
- the electricity to run the blankets may require the use of more energy resources than the resulting fuel savings.

- Leave Jack at home.
- may be illegal is some places.

- Advanced aerodynamics
- can only be done by the manufacturer before the vehicle is produced. To do it post-production may cost more than the fuel savings.

FINAL COMMENTS:
- While the hypermilers techniques may save fuel for the INDIVIDUAL hypermiler, it is very likely that the TOTAL amount of fuel used by ALL drivers may actually be HIGHER.

- in order to use less fuel across the whole economy there must be a drastic change is driving behaviour OR a drastic change in technology where all vehicles achieve the current FE of a stock Yaris.

Hypermiling is not a way to save the environment - its a SPORT. As such, it may be worth pursuing if it gives the participant a sense of accomplishment and pleasure. However, beyond the common sense techniques that drivers should know about anyway (and for whatever reason do not practice), hypermiling probably does not benefit society in general, and it may actually be detrimental as it leads other drivers to become more agravated thus taking this extra tension into their daily lives.

- I'm not sure if my savings of $1.60 for the week were worth the effort. Nevertheless, in order to pursue the SPORT I will try other techniques in the future. Up next, increase the tire pressure to 40psi and grow a thicker skin so that I'm not bothered when women give me the finger for gliding to a clear red light up ahead. Don't laugh that happened last week. It appears people rather maintain speed, break hard, and stand still at the light for two minutes than come to a slower stop and wait less than 10 seconds - go figure

That's the end of my rant. If you made it this far thank you for listening.
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Old 06-01-2007, 11:56 AM   #18
Astroman
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Drives: 07 Toyota Yaris, 71 Galaxie
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That was a nice, objective post. It is only proper to look at the cons as well as the pros. Well done. Sometimes those techniques are not practical in certain situations. My route to and from work (before 8 and after 5) do not permit much of a chance to hypermile. The speed limit is 30mph, but most do 37-45mph so using DFCO on what little hills there are with that much traffic is pretty much impossible. I do shut the engine off at stoplights, but only if I'm not next for the light sequence, and usually turn the car back on about 10 sec. before my light will change so I don't have a Yukon pushing me into the intersection. Usually if I'm a couple of cars back and the light changes I have enough time to start the car back up and put it in gear before the cars in front of me have really started moving. But, say if its after 7pm, that same route leaves lots of room for using DFCO, or even shutting the engine off. I'm not worried about the legality of this because my Yaris is so quiet anyway. And as for leaving the jack at home that is perfectly legal in WA. In fact, you don't even need a windshield! But you do have to have wipers . Anyway, great objective writeup. Well written. I will continue to do what I can to reduce the thinning of my wallet. SUVs can suck my ass.
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