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MPG experiment

2652 Views 17 Replies 11 Participants Last post by  Flyboy
Today, in an attempt to answer for myself whether Econ mode really does all that much, I did an experiment a little different than running a tank in Econ, then one without. I did as close to identical 10 mile runs as I could on a limited access highway. I entered the highway, accelerated to 70 MPH, set cruise control, then reset trip B at the first mile marker I came to. This mile marker was my start point for both runs so as to have identical terrain for both trips. Yes, after the first trip I went back and did it over without Econ. Fortunately, for both runs I didn't have to slow down for traffic. Both runs were with A/C off, and ambient temp 68-69 degrees with a slight head wind near as I could tell from the one flag I saw. Bottom line was I tried to keep conditions for both runs identical. I got 32.7 MPG with Econ and 32.4 without. Then I filled up to run one tank with Econ and the next without.

Which method do you guys think is the more accurate?

One tip for anyone wanting to try my method: I learned you can only hold the reset knob for the trip meter for a few seconds to reset it. If you hold it longer, about 5-10 seconds, it will continue on like you didn't even push it.
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I have been conducting my own real world driving experiment. I have driven the car to and from work every work day since I bought it with some driving on the weekends. I have been posting my mileage on fuelly.com and here are the results including the car's computer milages.

9/18 30.6 MPG Econ on 32.1 MPG Computer
8/29 31.5 MPG Econ off 32.0 MPG Computer
8/13 30.5 MPG Econ off 30.8 MPG Computer
7/26 31.1 MPG Econ on 32.3 MPG Computer
7/14 29.2 MPG Econ on

Fuelly results were obtained by dividing the number of gallons purchased into the miles driven.
The car's computer displays some interesting differences. The car computer shows a little better mileage on two tanks with Econ on and one about the same with Econ off. The computed mileage doesn't seem to make any real difference.
Here is a photo of two trips to work today. The previous one is driving to work in the morning and the current one is returning home on the same route. The morning commute had less traffic than the evening but the difference in the mileage is tremendous.

Anyone have a good explanation of the differences?

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Before starting any experiment, you should understand how the ECON mode works. What ECON or Sport mode does is change the transmission shifting behavior. ECON shift early and Sport shift later compare to the normal transmission shifting behavior. Therefore, ECON is not going to make any difference in a constant speed drive because there is no shifting involve. In order word, ECON probably will only improve gas mileage in a city drive.
Dont forget econ also retards throttle input
I have been conducting my own real world driving experiment. I have driven the car to and from work every work day since I bought it with some driving on the weekends. I have been posting my mileage on fuelly.com and here are the results including the car's computer milages.

9/18 30.6 MPG Econ on 32.1 MPG Computer
8/29 31.5 MPG Econ off 32.0 MPG Computer
8/13 30.5 MPG Econ off 30.8 MPG Computer
7/26 31.1 MPG Econ on 32.3 MPG Computer
7/14 29.2 MPG Econ on

Fuelly results were obtained by dividing the number of gallons purchased into the miles driven.
The car's computer displays some interesting differences. The car computer shows a little better mileage on two tanks with Econ on and one about the same with Econ off. The computed mileage doesn't seem to make any real difference.
Here is a photo of two trips to work today. The previous one is driving to work in the morning and the current one is returning home on the same route. The morning commute had less traffic than the evening but the difference in the mileage is tremendous.

Anyone have a good explanation of the differences?
I go to work at 4:45 AM and go home at 3:00 PM. I get between 35 and 38 MPG in the AM and about 32-33 in the afternoon. I leave econ on all the time. Set cruise at 60 MPH. More traffic in the afternoon - almost none in the morning. 30 miles each way, 90% highway. V6.
With those figures I hope that's a V6?
I always have around 200 miles with half a tank (the middle mark). Any one has better? :(
With those figures I hope that's a V6?
No, it's an I4. Why would you think that those numbers are from a V6?
Before starting any experiment, you should understand how the ECON mode works. What ECON or Sport mode does is change the transmission shifting behavior. ECON shift early and Sport shift later compare to the normal transmission shifting behavior. Therefore, ECON is not going to make any difference in a constant speed drive because there is no shifting involve. In order word, ECON probably will only improve gas mileage in a city drive.
Since this car has the CVT, there are no real shift points.
Since this car has the CVT, there are no real shift points.
He probably means simulated shift points. I understand what he means. The transmission does indeed 'shift' sooner with ECON ON and similarly holds 'gears' longer in SPORT.

There is no doubt that ECON works, see my signature for evidence.
There is no doubt that ECON works, see my signature for evidence.
I don't think anyone questions that ECON button works. However, based on the experiences of most (or at least, many) of us, the difference seems to be very minuscule.

I see that you achieved great mileage on a tank of gas that you mentioned and I am genuinely impressed. However, with all due respect, I don't see how that is a conclusive evidence that ECON always makes great difference in MPG under exact same conditions and/or for everyone, in light of numerous reports to the contrary. I mean, I am certain that you don't get 43.3 MPG combined on every tank where you turn on ECON.

Tell me if you disagree.

Mick
I just made a trip 200 miles. Cruise control at 70-75 whole way. Towards the end of the trip I really had to use the restroom so I started gunning it. And combined (computer) mileage showed at 34.3 without econ on. I agree though, I have inky noticed difference with econ in city driving. Youll notice a bit more hesitation, and the light around the speedo stays green more during normal acceleration. Either way. For a car with almost 300 hp, anything between 30-40 mpg is amazing to me.

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I just made a trip 200 miles. Cruise control at 70-75 whole way. Towards the end of the trip I really had to use the restroom so I started gunning it. And combined (computer) mileage showed at 34.3 without econ on. I agree though, I have inky noticed difference with econ in city driving. Youll notice a bit more hesitation, and the light around the speedo stays green more during normal acceleration. Either way. For a car with almost 300 hp, anything between 30-40 mpg is amazing to me.

Sent from AutoGuide.com Free App
If you have the V6 and you are cruising on the highway, your car is only running on three cylinders most of the time. That's how Honda was able to get the great highway mileage.
My question is why would there be such a huge difference between driving on the same route with more traffic than with less in the morning? The 39.1 miles per gallon reading was in the morning when there was almost no stop and go traffic at an average speed of about 55 mph. The 31.5 was achieved while creeping along in some traffic for about a third to half of the trip. The difference seems unbelievable versus the consistent over all milage of about 30 mpg.
My question is why would there be such a huge difference between driving on the same route with more traffic than with less in the morning? The 39.1 miles per gallon reading was in the morning when there was almost no stop and go traffic at an average speed of about 55 mph. The 31.5 was achieved while creeping along in some traffic for about a third to half of the trip. The difference seems unbelievable versus the consistent over all milage of about 30 mpg.
I have the same results as you(I4 EX-L Sedan). Mornings are not less than 40mpg, back to home is around 30-36mpg. I live in FL, so it seems like it depends on temperature, humidity etc. Also traffic is worse when I drive home.
I noticed this thing with my Prius gen 1. I was getting more than 51mpg when it is 75-78 degrees. When is too hot or too cold, mpg is way worse.

By the way, I drove with ECON button ON until 3800 miles, I turned it off and all my jerking/studdering are gone. Weird. No jerky stops also. Econ mode is like driving a Prius. I get same MPG with Econ off , it depends how you push gas pedal, imho.
I have the same results as you(I4 EX-L Sedan). Mornings are not less than 40mpg, back to home is around 30-36mpg. I live in FL, so it seems like it depends on temperature, humidity etc. Also traffic is worse when I drive home.
I noticed this thing with my Prius gen 1. I was getting more than 51mpg when it is 75-78 degrees. When is too hot or too cold, mpg is way worse.

By the way, I drove with ECON button ON until 3800 miles, I turned it off and all my jerking/studdering are gone. Weird. No jerky stops also. Econ mode is like driving a Prius. I get same MPG with Econ off , it depends how you push gas pedal, imho.
I have never seen 40 MPG on the computer. The highest I have seen is 39.1 One guess is that in the mornings the AC compressor may be operating less because of the cooler weather.
I can only get upper 40's and low 50's with ECON ON (not talking about instantaneous mpg, but trip mpg). My best trip in excess of 50 miles was just a tad over 50 mpg, but with ECON OFF I haven't seen better than low 40's. Maybe it's me being a lead food, perhaps others can get near 50 mpg with ECON OFF but I can't.
I can only get upper 40's and low 50's with ECON ON (not talking about instantaneous mpg, but trip mpg). My best trip in excess of 50 miles was just a tad over 50 mpg, but with ECON OFF I haven't seen better than low 40's. Maybe it's me being a lead food, perhaps others can get near 50 mpg with ECON OFF but I can't.
I am amazed at your mileage. I assume to get that mileage you were driving on the highway at a steady low speed.
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