Love your wallet: eleven fuel saving tips to put money back in your pocket
Over the last few years fuel prices, and by extension vehicle economy, have come into focus as a major factor for a lot of household's budgets. Think about for a moment what percentage of your weekly budget disappears into the tank. Now, would you like some of that back? Its easier than you think if you follow some simple rules that don't include driving everywhere at 30 mph.
For a few extra dollars in your pocket at the end of the week, make sure you follow these helpful tips published by The Daily Herald:
- Keep the car in as high a gear as possible and get to the higher gears as quickly as possible.
- Have a light touch on the throttle. For most applications 25 per cent throttle is quite adequate. Hard acceleration is the enemy of fuel economy.
- Look ahead and read traffic conditions. Plan to maintain momentum, reducing the need for excessive braking and subsequent acceleration.
- Monitor tyre pressures. Low pressures increase rolling resistance of tyres and use more fuel. You should keep to the manufacturer's specifications.
- Stick to the speed limit. High speeds use more fuel.
- Reduce mass and drag. You would be surprised how much unnecessary equipment accumulates in the boot of a car. Roof pods, racks and extended wing mirrors all minimise the efficiency of a car through the air. More weight and drag equals less economy. Remove the bits when they are not being used.
- Avoid idling as you are wasting fuel going nowhere.
- Keep your vehicle in shape; clean air filters keep impurities in the air from damaging the engine and can improve fuel economy.
- Don't turn on the air conditioner as a first response to heat; even the most efficient air conditioners expend a fair bit of fuel.
- When buying a car, consider its fuel economy.
Analysis: Ditching the roof racks and turfing out the bullion hidden in your boot is a no-brainer, but remembering that low gears, air conditioning and hard acceleration are fuel economy killers is the key in the long run. If we all held off the lead shoe for a week maybe we could put a dent in those Exxon profits?
Related:
[Source: Daily Telegraph]
Reader Comments (Page 1 of 1)
beeri 12:12PM (2/14/2007)
What is better: to floor it for 5 seconds then cruise for 30 seconds? or slightly depress the pedal for 35 seconds?
I heard that's better because the engine operates most efficiently at %100 throttle...
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Leszek Pawlowicz 2:15PM (2/14/2007)
2. Too light a touch on the throttle can sometimes waste gas. Accelerating from a full stop, the usual advice is to do it slowly, as if you have an egg between your foot and the gas pedal. But studies have shown it's more efficient to depress your pedal about two-thirds when accelerating from a stop, shifting to a more-efficient higher gear as quickly as possible.
4. Tire pressure is important, but more for safety than fuel economy. The oft-quoted figure of "1% drop in MPG for every 2 psi a single tire is underinflated" is wrong. The EPA now says that you lose about 0.5% in MPG for every 1 psi all four tires are underinflated. This is consistent with Consumer Reports and Edmund's findings that grossly underinflated tires (25% less than the recommended values) only cut mileage by about 1 MPG.
5. According to DOT studies, peak MPG occurs at around 55-60 MPH, but MPG is fairly flat from around 30 MPH to 60 MPH.
8. Consumer Reports looked at the effect of clogged air filters not that long ago, and found no difference in MPG between clean and clogged filters. The reason, they discovered, was that the car's computer compensated for the reduced air intake by reducing the amount of gas it fed to the engine. So MPG stayed the same, but performance suffered - acceleration wasn't as good. This is in contrast to the claim that a clogged air filter can cost you up to 10% in fuel efficiency.
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MetroMPG.com 2:37PM (2/14/2007)
If you want hardcore, in-depth discussion & answers about fuel efficient driving techniques:
http://gassavers.org
http://cleanmpg.com
Leszek, fuel economy is anything but "flat" at any constant speed between 30 and 60 (and beyond). Assuming you can be in top gear beyond 30, it drops predictably the faster you drive:
http://www.metrompg.com/posts/speed-vs-mpg.htm
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Chris M 9:01PM (2/14/2007)
No, "100% throttle" is NOT the most efficient for gas engines, maximum efficiency is well below maximum power output for gas engines.
It is different for electric motors, they are efficient through a wide speed and power output range. The result is some hybrids and electrics can get great fuel economy with "brisk" acceleration, when most power is electric.
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MikeW 3:08PM (2/15/2007)
The problem with 100% throttle is that there isn't a way to prevent acceleration enrichment. That was the issue with Edmunds test of GM's pickup. It stayed stoichometric for only four seconds.
GM should have kept it stoichometric while using tow/haul mode. Or have a throttle by wire system like BMW's. You can use full throttle in the manumatic gate without automatic downshifting, but if you push past the full throttle stop, the programming interprets that as an emergency, so full speed ahead.
Once the throttle gets to 60 degrees, the pumping losses are reduced, markedly. (nice laminar air flow around the throttle plate)
The 'egg between your foot' was from carburetor days, same with the 'clogged air filter 10% mileage loss' and older tires (non radial tires) suffering larger losses at reduced tire pressures.
Certain cars do have a flat fuel economy graph. As the engine speed increases, the BSFC drops, and the allowable percentage of EGR increase, so you can drive 60 or 80mph and get the same mileage.
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Bison 10:40AM (7/05/2007)
WOT/Short-Shifting article on R&T:
http://www.roadandtrack.com/article.asp?section_id=20&article_id=3424&page_number=3
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