Fuel Economy

[swng]

Originally Posted by Nigal

I was getting 34-37MPG when I first got mine but it slowly got better as I put more miles on.

Seems to be a common trend.

[ChinoCharles]

308.46 miles
7.365 gallons
41.9 MPG
95% city driving
Shell 87

[glxBoSS]

Wow... Impressive, maybe I'll get up to them numbers once I break my lil car in Charles.

[ChinoCharles]

I'm impressed myself. That is a 10 MPG increase from the first tank I logged on the car. I took on some driving techniques straight from the hypermilers and its working well for me. I'm not turning the car off while moving or anything. I'm smarter than that. What I am finding is that you can shift at 1500-2000 RPM in this car all day without having to use too much gas to compensate. As most of my driving is done in 35-45 MPH zones chocked full of stop signs, I find that when accellerating from a stop it is beneficial to give each gear until about 2000 RPM and shift. That puts you in second at 10 MPH, third at 20 MPH, fourth at 30 MPH, and fifth at 40 MPH. On my next tank I am aiming for 45 MPG. I have a couple mods on the way that may help me even further in my newfound quest to stick it to the Saudis. Stay tuned.

[Nigal]

I remember hearing that BMW did a study to determine at what RPM gets the best MPG and they found that shifting below rpm gets better than higher rpms. This last tank full I simply cut my speed by 10 mph; 65 from 75 on four lanes and 55 from 65 on two lanes. As of last night I had 300 and it just fell below the half tank mark. I drive a rout for work so it's the same every day. The strangest thing is that I still arrive at my destination at almost the exact same time as when I speed. I'll report back when I do my fill up and report my mileage.

[Racer X-8]

Originally Posted by Nigal

... The strangest thing is that I still arrive at my destination at almost the exact same time as when I speed. ...

Not so strange, for 2 reasons:

1. If you pass thru a series of traffic lights, they could be programmed and will stop you if you're over the speed limit. I could bore you with a long story about me versus a Greyhound bus that was in a hurry late one night,,, just believe it.
2. 10 miles @ 55mph = 10 minutes, 55 seconds. 10 miles @ 80mph = 7 minutes, 30 seconds. The 10 mile difference = 3 minutes, 25 seconds. Using "you" generically---> Now you have to ask yourself "Is 3-1/2 minutes worth it?" The answer to that should almost always be "NO". Heck, a visit to the restroom would use-up all of that. If you're late to get to work, would 3-1/2 minutes really matter that much? How about you leave home on-time and not try to make it up by driving dangerously. <--- Using "you" generically.

[ojo]

I've had my Yaris for a little over a month, and I have to say that I am very happy with my mileage so far. I got 34.5 mpg on the first tank and have gotten 35-37 since then. I drive 35 miles one way to work and drive about 70-75 mph. I definitely notice a difference in mileage when I floor it at a green light, but when I accelerate more smoothly and gradually, I can keep good mileage while still driving semi-aggressively.

[Nigal]

Originally Posted by Racer X-8

Not so strange, for 2 reasons:

1. If you pass thru a series of traffic lights, they could be programmed and will stop you if you're over the speed limit. I could bore you with a long story about me versus a Greyhound bus that was in a hurry late one night,,, just believe it.
2. 10 miles @ 55mph = 10 minutes, 55 seconds. 10 miles @ 80mph = 7 minutes, 30 seconds. The 10 mile difference = 3 minutes, 25 seconds. Using "you" generically---> Now you have to ask yourself "Is 3-1/2 minutes worth it?" The answer to that should almost always be "NO". Heck, a visit to the restroom would use-up all of that. If you're late to get to work, would 3-1/2 minutes really matter that much? How about you leave home on-time and not try to make it up by driving dangerously. <--- Using "you" generically.

[whine] Math is hard and stuff... LOL!

I've been trying to leave home about 5-10 minutes early to make the difference. One of the best things about driving slower is that I don't end up stuck behind the damn soccer moms in minivans going 65 in the fast lane.

[swng]

Originally Posted by Nigal

[whine] Math is hard and stuff... LOL!

I've been trying to leave home about 5-10 minutes early to make the difference. One of the best things about driving slower is that I don't end up stuck behind the damn soccer moms in minivans going 65 in the fast lane.

Very sensible friend!
BTW, I would take the opportunity and sidetrack a bit to mention that one of the safe ways to save fuel is not to follow the car in front too closely (aka tailgating). Whilst taking advantage of the draft created by the car in front is good when everything is on the move, tailgating, especially in city driving conditions, will usually result in a need to brake repeatedly and abruptly, and will prevent the use of good anticipatory driving techniques. Such are hardly good for fuel economy.

[leowhy]

Originally Posted by swng

Very sensible friend!
BTW, I would take the opportunity and sidetrack a bit to mention that one of the safe ways to save fuel is not to follow the car in front too closely (aka tailgating). Whilst taking advantage of the draft created by the car in front is good when everything is on the move, tailgating, especially in city driving conditions, will usually result in a need to brake repeatedly and abruptly, and will prevent the use of good anticipatory driving techniques. Such are hardly good for fuel economy.

unfortunately that is not possible in where i live... the traffic here is bumper to bumper situation...

[Nigal]

i don't draft. With my attention span and the weakness of the body panels in this car I'd end up with a 1.5 liter engine in my lap with my legs cureled around it.

I did fill up yesterday and with the new slower driving I've been doing I got like 42.4 mpg. I got the stock tires pumped up to 44 psi now and will see what kind of difference it makes if any.

[BailOut]

The world was out to kill my FE on this tank (colder temps, rain, snow, high winds, etc.), and the wife put 75 miles of errands on it while we're caring for a family dog in another part of town, but I managed to salvage 49.463 MPG out of it.

[swng]

Originally Posted by leowhy

unfortunately that is not possible in where i live... the traffic here is bumper to bumper situation...

IMHO, when the traffic is very slow, it is OK to follow the car in front closer. So in your situation, it may not necessarily mean that you have been tailgating. There is always a need to give yourself at least two seconds to react to whatever that may happen suddenly though (such as the car in front braking abruptly). Incidentally, doing this may also boost your FE slightly.
Safe and happy motoring!

[swng]

Originally Posted by Nigal

i don't draft. With my attention span and the weakness of the body panels in this car I'd end up with a 1.5 liter engine in my lap with my legs cureled around it.

I did fill up yesterday and with the new slower driving I've been doing I got like 42.4 mpg. I got the stock tires pumped up to 44 psi now and will see what kind of difference it makes if any.

Nice to learn about that. The mpg numbers are good and apparently already better than EPA ratings (http://www.epa.gov/otaq/cert/mpg/overall-high.htm ) granted that it has basically been day to day driving that has helped achieve them. Thumbs up!
On the other hand, over pumping the tires may result in the treads in the middle wearing faster. I do not know how far the tires have to be over inflated for this to occur. Intuitively, I think the tires will have to be significantly over inflated for any uneven tread wear to become noticeable in a short span of time. I can be wrong. Anyway, if uneven tread wear does occur, then there may be a need to weigh between the cost of the fuel saved and the cost of the tires to the extent that they may need to be replaced prematurely in order to be safe.
Any input will be most welcome.
Safe and happy motoring!

[leowhy]

Originally Posted by swng

IMHO, when the traffic is very slow, it is OK to follow the car in front closer. So in your situation, it may not necessarily mean that you have been tailgating. There is always a need to give yourself at least two seconds to react to whatever that may happen suddenly though (such as the car in front braking abruptly). Incidentally, doing this may also boost your FE slightly.
Safe and happy motoring!

that is what i've been doing... :)

the frustrating part is, many other road user just utilise the "gap" i leave for me & CUT IN!!!

in the end... its E_brake + accelerate time again...

[swng]

Same happens to me leowhy. I know how you feel. By and by, I have learned even to anticipate what that kind of drivers will do and avoid situations that would necessitate wasting too much fuel to match their movements. There is always a limit as to what one can do anyway. The bottom line is when forced to choose between safety and FE, we should always choose safety.
Thanks for the response again.

[swng]

Originally Posted by swng

Filled up on 2 Jun 07 and the result was:

About 563 km traveled. Consumed 38.096 liters of fuel and used C$42.82 to fill back up.
Approximately 41.76 mpg (Imperial), or about 34.76 mpg (US), or 14.78 km per liter, or 6.77 liters per 100 km. I occasionally carried three passengers with their belongings, and the A/C was used about half of the time. Weather was good but warm. Driving style was - keep pace with traffic and be fuel economy conscious. No exotic measure used to save extra fuel. Other conditions similar to last report quoted i.e. Post #1201 at P.81.

This time, I used this free calculator (except for mpg (US)) which also contains a pageful of usual fuel saving tips:

http://www.vehicleservice.co.za/calc/fuel.html

For the mpg number in US gallon terms, I used the calculator provided free here:

http://www.gassavers.org/garage/viewgaslog/264

Latest tank's result:
About 38 mpg (Imp), or 31.69 mpg (US) or 13.47 km per liter.
The car was driven by my brother most of the time. I am not surprised by the drop in mpg considering the people and golf clubs he carries.
I am glad that the result is still above the EPA average.
Last report at Post #1246.

[keesue]

I'm now getting 40 mpg consistently at 70 mph max speed - up from 36.5. I have 9,100 miles on the car and its an Automatic. It is used predominately as a commute vehicle with 65 mph average speeds on the freeway - some hills with a bit of city on both ends. The car is all stock - no changes. I'm considering running Royal Purple 5w-20w. Also considering a CAI to open up the throat. In every car I have owned, these two things were the single most noticable improvement in fuel efficiency - as long as the right foot didn't cancel it out. (A free-flowing exhaust also helped but I don't want the noise in this one).

I have read the threads posted herein on the subject of fuel gains with a CAI and there appears to be no agreement. I'm wondering if there is a cancelation affect as the ECU adjusts the fuel and air ratio thereby making the gain in hp/torque that does not necesarily translate into better mpg. I would think that efficiency gain would result in mpg gains. I'm not sure about this as my past cars were not controlled by computer. I think I need to delve into this a bit more. I would expect a modest increase but would need to know a number to justify the ROI. Having said that, its time to lower the car. This, of course, would be sans ROI - just looks...heh.