SickBeast's Fuel Economy Guide

Status
Not open for further replies.

SickBeast

Lifer
Jul 21, 2000
14,377
19
81
Ok, I've let this go on long enough. If you guys want to argue about crash tests make a new thread. This one is so derailed, I'm locking it up. Feel free to repost it if you want but it will not get a sticky.

Anandtech Moderator
Gillbot



I have decided to create this thread for a number of reasons. To make a long story short, a lot of people ask about how to improve their fuel economy, plus gas isn't getting any cheaper. So, here is what I have so far, and please keep in mind that I am not responsible for anything bad that may come out of these tips and techniques:

1. Inflate your tires to the 'reccomended' rating. If you're brave, over inflate them a bit. *Warning* This can be dangerous, particularly if you do not know the condition of your tires. It is akin to overclocking your CPU! Do it slowly in very small increments and NEVER go more than a few PSI over! Thank-you Ronstang for the information! *further edit* PhoKingGuy has made an excellent point in the sense that if you overinflate your tires, you will have less surface contact with the road, which will put your life in danger in an emergency. I am tempted to remove this entire part of the guide. This is extremely dangerous - please do this at your own risk with the utmost caution. Further to that, if you have really "fat" tires (racing tires), then over-inflating them is not really going to do anything because it will remove a smaller percentage of surface area (plus the car is probably already an animal to begin with). Thanks Yoxxy for a different perspective. My suggestion would be to never exceed the sidewall so that your car is driving around on "skates". :light:

2. Hypermiling. Never use your brakes unless you absolutely have to. Accelerate slowly. Use your cruise. Accelerate with your cruise control (the little +/- buttons near it). Watch the traffic lights ahead of you carefully and take your foot off the gas for stale green lights, yellow lights, and red lights. If you google this, there is a wealth of information.

3. Change your air filter every 20,000kms (12,400 miles). It's $20 at Wal Mart and will take 2 minutes to install yourself.

4. Maintain your car (oil changes especially).

5. Use good gas with good additives. Some say Shell is the best; I find here in Canada that Petro Canada and Ultramar are the best based on the 'feel' of my car.

6. Clean your fuel injectors periodically with a good tactrol additive. Gas has fuel injector cleaner in it by regulation, however it does not meet the recommended level. Essentially the gas companies cheaped out. My uncle is a mechanic and it is the one additive he recommended on a regular basis (every 2 months would probably be ideal). *note* Volkswagon does not recommend you do this. There may be other manufacturers as well, so please read your manual to make sure this is good for your car. I feel that many of these manufacturers have banned injector cleaner in error due to tighter fuel regulations in Europe (they add it to the fuel by default - that's how important this stuff is!). Thanks PhoKingGuy for the additional insight.

7. Put your windows up and close your sunroof if it's not too hot out and you don't need the fresh air. Having the windows down creates drag and makes your car less aerodynamic. *edit* This is not entirely necessary while travelling at low speeds. Thanks Turin39789 for the additional information.

8. Purchase low rolling resistance tires, especially if you do mostly city driving. Note that this may reduce your handling depending on the tires you had before, plus, they will not handle as well as an equivalently priced set of "regular" tires, particularly at highway speeds, in general. Technology may overcome this shortly. Yoxxy has subconsciously encouraged me to note that low rolling resistant tires are practically worthless if you have fat tires to begin with (racing tires).

9. Reduce the weight of your car. If you're brave enough, take out the spare tire and equipment from your trunk. Remove your air conditioner if you live in a cold enough climate. Beyond that, weight reduction tends to involve radical alterations, especially if the above options made you wary. Removing the AC and the tire will make your car weigh at least 100lbs less, though.

10. Pulse-and-glide. Accelerate around 10mph above your desired speed. Put the car in neutral and coast to 10mph below your desired speed. Repeat the cycle. Use your car's "resume" feature on the cruise if you can. I find that this works best going down a slight decline, especially if you are familiar with the road. *note* This may not be legal in your jurisdiction, so be careful.

11. Put the car in neutral at all red lights if you have an older automatic transmission. This will not only save you money on gas, but will save you wear on your transmission, engine, and brakes as well. Older autotragic cars try to "go" at the idle speed even if you have the brakes on. I have been made aware that modern cars have gotten around this with technology, however I cannot guarantee that all manufacturers have this technology. Thanks PhoKingGuy for some extra details.

12. Use neutral as much as possible. Coast to stop signs. Coast down hills. Again, be careful, this may not be legal in your area.

13. Use engine brakes to slow down. When your car is slowing down while in gear (manual transmission), there is no fuel in the motor at all, only air.

14. Use aerodynamic undersiding and install a "taller" transmission. The undersiding sounds reasonably simple. I guess if you need a new tranny you could ask about getting a taller one. *edit* Thanks fleabag for some new ideas and significant insight into tire pressure.

15. Aerodynamic mods. Thanks fleabag for the inspiration. As an aside, washing your car will make it marginally more aerodynamic.

16. This entire guide may be relatively useless to you, depending on the type of car you drive. Thanks DVad3r for pointing out that a 2001 Lexus ES 300 does not show much difference if any under hypermiling (driving style only I would assume).

Beyond that, I am open to suggestions.

I have managed to get 750 kilometers (466 miles) on a city tank of gas consistently in a very congested part of downtown Toronto using many of these techniques. This is in a regular 2006 Honda Civic; no hybrid at all.

You get used to your route to and from work along with the tricks you can use in different places.

Zenmervolt, I would appreciate a sticky. :beer:





Thanks for your efforts, but the mods have discussed this and we don't feel the information warrants a sticky. Some of your suggestions are controversial, to say the least.

Rio Rebel
Senior Moderator


Fair enough. I have updated the OP somewhat. Perhaps one day.
 
Last edited by a moderator:

punjabiplaya

Diamond Member
Nov 12, 2006
3,495
1
71
cruise control is fail for economy, especially if any elevation change is involved.
 

SickBeast

Lifer
Jul 21, 2000
14,377
19
81
Originally posted by: punjabiplaya
cruise control is fail for economy, especially if any elevation change is involved.

How so?

*edit* If you're going down a hill, you should have the car in neutral, but that is also in the guide. If you're going up a hill, the cruise can actually overload your car if it's old and crappy enough. With a modern car, however, I don't see the issue in cruising up a hill, provided it's not too steep.
 

Ronstang

Lifer
Jul 8, 2000
12,493
18
81
Please do not tell people to over inflate their tires. It is a very bad idea. The heat generated driving increases the pressure inside and can cause them to explode. Not all tires are created equal and although some may be able to handle the extra pressure some definitely will not. My dumbass friend learned this the hard way. When the tire exploded it blew the fender apart. He was damn lucky he wasn't killed.
 

SickBeast

Lifer
Jul 21, 2000
14,377
19
81
Originally posted by: Ronstang
Please do not tell people to over inflate their tires. It is a very bad idea. The heat generated driving increases the pressure inside and can cause them to explode. Not all tires are created equal and although some may be able to handle the extra pressure some definitely will not. My dumbass friend learned this the hard way. When the tire exploded it blew the fender apart. He was damn lucky he wasn't killed.

I put in a disclaimer for a reason. In my experience, over inflating the tires a *bit* makes a noticeable difference (50kms/tank if not more).

I'd say never over inflate tires in snowy conditions. In fact you might want them under inflated in the snow.

I will add a stern warning to the section. Thanks!
 

SickBeast

Lifer
Jul 21, 2000
14,377
19
81
On second thought I have drastically altered the section on tire inflation. Thanks for the voice of reason, Ronstang. People's lives are not worth a few extra miles on a tank of gas.
 

SickBeast

Lifer
Jul 21, 2000
14,377
19
81
More disclaimers added. Please make sure that running your car in neutral is legal in your area.
 

PhoKingGuy

Diamond Member
Nov 15, 2007
4,685
0
76
Originally posted by: SickBeast

2. Hypermiling. Never use your brakes unless you absolutely have to. Accelerate slowly. Use your cruise. Accelerate with your cruise control (the little +/- buttons near it). Watch the traffic lights ahead of you carefully and take your foot off the gas for stale green lights, yellow lights, and red lights. If you google this, there is a wealth of information.

If you do this, please stay in the right lane so I can pass you

6. Clean your fuel injectors periodically with a good tactrol additive. Gas has fuel injector cleaner in it by regulation, however it does not meet the recommended level. Essentially the gas companies cheaped out. My uncle is a mechanic and it is the one additive he recommended on a regular basis (every 2 months would probably be ideal).

Most car companies recommend not doing this, my VW manual directly states not to use any sort of injector cleaner

8. Purchase low rolling resistance tires, especially if you do mostly city driving.

If you value any sort of handling, you wont do this

9. Reduce the weight of your car. If you're brave enough, take out the spare tire and equipment from your trunk. Remove your air conditioner if you live in a cold enough climate. Beyond that, weight reduction tends to involve radical alterations, especially if the above options made you wary. Removing the AC and the tire will make your car weigh at least 100lbs less, though.

Seriously?? Just stop eating cheeseburgers

11. Put the car in neutral at all red lights if you have an automatic transmission. This will not only save you money on gas, but will save you wear on your transmission, engine, and brakes as well. Autotragic cars try to "go" at the idle speed even if you have the brakes on. Perhaps modern cars have gotten around this with technology, but I doubt it.

Wrong, modern automatics consume more gas in neutral than in idle, such was with all the cars I have driven. The engine seems to spin higher when you are in neutral anyway.

 

SickBeast

Lifer
Jul 21, 2000
14,377
19
81
By the way, PhoKingGuy, VW may not recommend the injector cleaner because in Europe they probably add the correct amount to the gas by default. Too much injector cleaner can burn out your injectors, which is why you do it periodically. It's made out of jet fuel. :Q
 

PlasmaBomb

Lifer
Nov 19, 2004
11,636
2
81
Originally posted by: Ronstang
Please do not tell people to over inflate their tires. It is a very bad idea. The heat generated driving increases the pressure inside and can cause them to explode. Not all tires are created equal and although some may be able to handle the extra pressure some definitely will not. My dumbass friend learned this the hard way. When the tire exploded it blew the fender apart. He was damn lucky he wasn't killed.

You sure it was because the tyre was over inflated? The increased pressure should reduce the flex and reduce the heat buildup compared to a lower psi. Granted if he did a hypermiler trick and went to 50+ PSI that is a different story - tyres have a maximum pressure* rating on them for a reason...

* 40 PSI for the tyre in question.

12. Use neutral as much as possible. Coast to stop signs. Coast down hills. Again, be careful, this may not be legal in your area.

This is wrong... I concur with PhokingGuy, idling in neutral increases the fuel consumption.

Do not coast down hills in neutral! It's dangerous and may very well be illegal.

Using engine braking to coast to a stop is fine, since the car should cut the fuel to the engine.
 

ja1484

Platinum Member
Dec 31, 2007
2,438
2
0
Injector cleaner really isn't necessary at all - especially if you use top tier gasoline. It used to be you could find a fair amount of low quality gasoline which was rather impure. That's much harder to do these days.

None of my buddies in mechanical and car service have reported tearing into an engine and finding deposits on/in the injectors. In fact, pretty much all of them state they have never seen any evidence for it. Modern cars with EFI will throw a CEL if there's an injection problem.

If the injector is clogged and dripping or not spraying at all, you're going to damn sure know it.
 

SickBeast

Lifer
Jul 21, 2000
14,377
19
81
Originally posted by: PlasmaBomb
12. Use neutral as much as possible. Coast to stop signs. Coast down hills. Again, be careful, this may not be legal in your area.

This is wrong... I concur with PhokingGuy, neutral fuel consumption is higher.

Do not coast down hills in neutral!

Using engine braking to coast to a stop is fine since the car should cut fuel.
First of all, you get the equivalent of 100+mpg when you're coasting in neutral.

Second, what I do is to coast in neutral if I want a long "glide". If I need to slow down/stop, then I leave it in gear to use engine brakes.
 

SickBeast

Lifer
Jul 21, 2000
14,377
19
81
Originally posted by: ja1484
Injector cleaner really isn't necessary at all - especially if you use top tier gasoline. It used to be you could find a fair amount of low quality gasoline which was rather impure. That's much harder to do these days.

None of my buddies in mechanical and car service have reported tearing into an engine and finding deposits on/in the injectors. In fact, pretty much all of them state they have never seen any evidence for it. Modern cars with EFI will throw a CEL if there's an injection problem.

If the injector is clogged and dripping or not spraying at all, you're going to damn sure know it.

Yeah but how sensitive is the CEL sensor? If an injector is 10% clogged, my guess is that the computer will think that it's within spec. I don't think a clogged injector would be visible to the eye. The tiny holes that spray the fuel get clogged. It's like a hose that sprays mist.
 

Bignate603

Lifer
Sep 5, 2000
13,897
1
0
Originally posted by: ja1484
Injector cleaner really isn't necessary at all - especially if you use top tier gasoline. It used to be you could find a fair amount of low quality gasoline which was rather impure. That's much harder to do these days.

None of my buddies in mechanical and car service have reported tearing into an engine and finding deposits on/in the injectors. In fact, pretty much all of them state they have never seen any evidence for it. Modern cars with EFI will throw a CEL if there's an injection problem.

If the injector is clogged and dripping or not spraying at all, you're going to damn sure know it.

Once I did have misfire due to a clogged injector. Those cleaners couldn't do anything to fix it. It took a professional cleaning by my mechanic to fix it.
 

franksta

Golden Member
Jun 6, 2001
1,967
6
81
Originally posted by: SickBeast
11. Put the car in neutral at all red lights if you have an older automatic transmission. This will not only save you money on gas, but will save you wear on your transmission, engine, and brakes as well. Older autotragic cars try to "go" at the idle speed even if you have the brakes on. I have been made aware that modern cars have gotten around this with technology, however I cannot guarantee that all manufacturers have this technology. Thanks PhoKingGuy for some extra details.


Untrue. My truck is designed to raise the idle speed when in neutral and park to provide more cooling air with the mechanical fan. Higher idle = more gas. What wear on the transmission? It might be warming up my trans fluid a little but not enough to worry about. The higher idle might even be washing down the cylinder walls, unlikely though. Brakes are a wear item. It's not like I'm cooking the tires while holding the car back against the brakes anyway.


I'd recommend you remove this from your list as it is BS.
 

Turin39789

Lifer
Nov 21, 2000
12,218
8
81
1. Overinflation is dangerous, a psi or two won't kill you thought.
2. Accelerate slowly, cruise isn't for mpg.
3. Change your air filter according to your manufacturer recommended guidelines
4. Change your oil ""
5. Gas is pretty much gas. Obsessing over brands is silly
6. Additives are generally unneccesary and/or snake oil. I don't know of any manufacturer that recommends them, if they thought the engine needed it they would try to sell it to you.
7. Windows up is good on highway, you lose about the same mpg with windows up highway as you do with the air on, around town windows down is fine.
8. Possibility, but I still haven't seen a consistent rating system/measurement for rolling resis
9. Yes less weight means less gas. Don't take out stuff you need, like a spare tire, but don't haul around that anvil in your trunk if you aren't going to be using it.
10. This sounds annoying and dubious. If you want to be annoying and effective, hold your go pedal steady and speed up on the downhill and let yourself slow down on the uphill.
11. No. I doubt this saves at all and you should be ready to manuever the car from the stop.
12. I do this in my manual. Not sure how much it helps.
13. Blag. Here's the trick, maintain your car by following your manual. Don't zip around like a loon and use your brakes when you don't need to. Brakes eat up accelration you already paid for in gas, but don't put anyone in danger trying to save $1.28. Leave a following distance in traffic so you don't have to hit the brakes everytime someone in front of you does. Accelerate slowly, like you have an egg under the pedal.
 

thescreensavers

Diamond Member
Aug 3, 2005
9,916
2
81
My parents hate the way I drive on the highway, they think that if the car in front of me has there brake lights on I need to break also. I always have enough following distance, so sometimes it closes the gap up a bit but usually they will get back on the gas before I get close enough to have to brake. If I do start getting too close I will hit my brakes.


Am I driving wrong? I don't think so. Brakes = loss of mpg!

I am suppose to inflate all my tires to 32, but I do Front 32 Rear 35. I have no idea if that even helps me much on mpgs lol.
 

JulesMaximus

No Lifer
Jul 3, 2003
74,534
911
126
Originally posted by: SickBeast
Originally posted by: punjabiplaya
cruise control is fail for economy, especially if any elevation change is involved.

How so?

*edit* If you're going down a hill, you should have the car in neutral, but that is also in the guide. If you're going up a hill, the cruise can actually overload your car if it's old and crappy enough. With a modern car, however, I don't see the issue in cruising up a hill, provided it's not too steep.

No, you shouldn't. Modern fuel injected cars shut off the injectors completely when coasting in gear as the wheels are basically driving the engine at that point. Put it in neutral and the engine has to use fuel to keep running.
 

The-Noid

Diamond Member
Nov 16, 2005
3,117
3
76
This is the dumbest list ever.

I have my tyres at 45/45.

Downwind I can get 21 MPG on the highway and 10 in the city with my daily driver. But I also have 505 BHP and 420 lb/feet, so it is a tradeoff.

If you want fuel economy buy a TDi.
 

BassBomb

Diamond Member
Nov 25, 2005
8,390
1
81
10. has never worked well for me (tested in 07 Accord, 02 Civic, 07 ES350 all automatic)

 

ElFenix

Elite Member
Super Moderator
Mar 20, 2000
102,358
8,447
126
real list:
maintain your car in accordance with the manual
get all that crap out of the back seat and the trunk
don't race from stop light to stop light


the only thing cruise is good for (gas mileage-wise) is keeping you from drifting upward in the mph department. it has a tendency to race uphill, which isn't good for mileage.
 

jlee

Lifer
Sep 12, 2001
48,518
223
106
10. Pulse-and-glide. Accelerate around 10mph above your desired speed. Put the car in neutral and coast to 10mph below your desired speed. Repeat the cycle. Use your car's "resume" feature on the cruise if you can. I find that this works best going down a slight decline, especially if you are familiar with the road. *note* This may not be legal in your jurisdiction, so be careful.

I would stop you for speeding and erratic operation. Coasting in neutral is also illegal in my state. FWIW.
 

angry hampster

Diamond Member
Dec 15, 2007
4,232
0
0
www.lexaphoto.com
I have a feeling that you're the kind of driver that I HATE being stuck behind, Sickbeast. Everything on your list may be good for ~10% improvement in fuel economy in conventional vehicles. A lot of it is dangerous and also entirely useless. You're a misinformed, cheap bastard.
 

alpineranger

Senior member
Feb 3, 2001
701
0
76
Originally posted by: PlasmaBomb
Originally posted by: Ronstang
Please do not tell people to over inflate their tires. It is a very bad idea. The heat generated driving increases the pressure inside and can cause them to explode. Not all tires are created equal and although some may be able to handle the extra pressure some definitely will not. My dumbass friend learned this the hard way. When the tire exploded it blew the fender apart. He was damn lucky he wasn't killed.

You sure it was because the tyre was over inflated? The increased pressure should reduce the flex and reduce the heat buildup compared to a lower psi. Granted if he did a hypermiler trick and went to 50+ PSI that is a different story - tyres have a maximum pressure* rating on them for a reason...

* 40 PSI for the tyre in question.

Underinflation is much more dangerous than overinflation. Tire manufacturers always caution against underinflation, but I have never seen any explicit warning against overinflation. In fact, if you want the tires to perform to their rated specifications as far as speed and loading goes, you must inflate to the sidewall pressure.

Underinflation causes tire failure by increasing the heat generated in the tire (from increased tire flex). The more inflated the tire is (and the less is asked from it in terms of speed and loading) the less heat is generated. Even a large amount of heat will not raise the pressure enough to cause anything close to failure unless the tire is grossly overinflated by many times what the the sidewall limit is.

What are the problems with overinflation? 1) really rough ride, and increased wear on other suspension components 2) reduced contact patch, which means many things - compromised handling and uneven wear.
 
Status
Not open for further replies.
sale-70-410-exam    | Exam-200-125-pdf    | we-sale-70-410-exam    | hot-sale-70-410-exam    | Latest-exam-700-603-Dumps    | Dumps-98-363-exams-date    | Certs-200-125-date    | Dumps-300-075-exams-date    | hot-sale-book-C8010-726-book    | Hot-Sale-200-310-Exam    | Exam-Description-200-310-dumps?    | hot-sale-book-200-125-book    | Latest-Updated-300-209-Exam    | Dumps-210-260-exams-date    | Download-200-125-Exam-PDF    | Exam-Description-300-101-dumps    | Certs-300-101-date    | Hot-Sale-300-075-Exam    | Latest-exam-200-125-Dumps    | Exam-Description-200-125-dumps    | Latest-Updated-300-075-Exam    | hot-sale-book-210-260-book    | Dumps-200-901-exams-date    | Certs-200-901-date    | Latest-exam-1Z0-062-Dumps    | Hot-Sale-1Z0-062-Exam    | Certs-CSSLP-date    | 100%-Pass-70-383-Exams    | Latest-JN0-360-real-exam-questions    | 100%-Pass-4A0-100-Real-Exam-Questions    | Dumps-300-135-exams-date    | Passed-200-105-Tech-Exams    | Latest-Updated-200-310-Exam    | Download-300-070-Exam-PDF    | Hot-Sale-JN0-360-Exam    | 100%-Pass-JN0-360-Exams    | 100%-Pass-JN0-360-Real-Exam-Questions    | Dumps-JN0-360-exams-date    | Exam-Description-1Z0-876-dumps    | Latest-exam-1Z0-876-Dumps    | Dumps-HPE0-Y53-exams-date    | 2017-Latest-HPE0-Y53-Exam    | 100%-Pass-HPE0-Y53-Real-Exam-Questions    | Pass-4A0-100-Exam    | Latest-4A0-100-Questions    | Dumps-98-365-exams-date    | 2017-Latest-98-365-Exam    | 100%-Pass-VCS-254-Exams    | 2017-Latest-VCS-273-Exam    | Dumps-200-355-exams-date    | 2017-Latest-300-320-Exam    | Pass-300-101-Exam    | 100%-Pass-300-115-Exams    |
http://www.portvapes.co.uk/    | http://www.portvapes.co.uk/    |