I tried to drive a full day with eco button on and another day with it off... car saved way more gas and more responsive with eco button off.. is there a certain time I'm supposed turn it on for best gas mileage?

 

I'll admit I don't see much difference either. I use the ECON button for smoothness and refinement, and turn it off for more responsiveness as needed.

 

You got better mileage with ECON off? Were the conditions for both days exactly the same? Were you running the AC? What is your driving style (easy on the gas or furiously speeding)?

 

The ECO mode is supposed to dull response of the powertrain to encourage better fuel economy. Not sure why you didn't see a difference, unless you were overcompensating for the duller response by mashing the gas more than you did without it lol.

 

My experience - with 5 fuel ups was as follows:


First Tank - ECON on all the time --- ~ 34 mpg
Second Tank - ECON on all the time -- again just about 34mpg


Both of the above reading were under the same operating conditions which is mostly suburban driving environment


Third tank - ECON off all the time --- 28.4 MPG --- again under same driving conditions .... From my brief experiment I found that ECON on did improve mileage.


Fourth Tank - ECON back ON --- mostly highway driving my mileage was 35.5mpg
Fifth - ECON ON --- 34.3 MPG --- again mostly suburban area driving


I'd suggest you try driving with ECON ON for a whole tank of gas and then try using ECON off for a whole tank of gas to see the differences... Also do not trust the onboard computer --- it definitely can be very inaccurate -- I have seen 2-4MPG difference between real world "calculated" gas mileage and the onboard system...

 

The econ button seems to be a waste of a switch and space. If you set your cruise at 55 and brake down to 45 you won't believe how long it will take to get back to 55 with econ on. I would just think of it as a picture of a plant on your dash. LOL

 

The ECON button will save more fuel if you are running the AC. ECON will cycle the compressor off until the ventilated air starts to warm, then it turns the compressor back on to cool the air again. As it cycles off and on, you save fuel during the off cycle because the engine load is reduced. I do notice the AC is less effective with ECON on, but its fine. If I am sweating my balls off I will turn ECON off until I cool down.

To answer your thread topic question, the proper use of the ECON button is to leave it on all the time. If you need an artic blast from the AC, turn it off temporarily. If you need more power, just shift into sport mode or paddle shift. That's just my opinion. Another valid opinion would be to say not to use the ECON mode. We need more data on how much fuel it saves.

 

I mean to try Sport with ECON. Thanks for the reminder. That may be just the ticket.


I've used the paddles a few times, on this car and other cars with them. To me they are like teats on a bull. Give me a manual or an automatic.

 

It helps you drive more economically on gas by easing the throttle. If you want to save gas, just drive more like you would in a hybrid vehicle: no rapid acceleration, coast as much as possible especially up to lights/stop signs, use the accelerator as little as possible, etc.

Or just turn ECO on, leave it on, don't drive faster than the speed limit, don't accelerate more than neccessary and in general you'll get better MPGs.

 

I use mine when I'm on the highway and set the cruise control. I did a trip to East Dorset, VT last weekend and got 51 and change.

 

I watched this same discussion on the CR-Z forum three years ago, where the majority of those testing found the same thing the OP found. The Econ button causes the car to use more fuel. True it dulls throttle response, and that just leads to the engine operating less efficiently. Counter-intuitive, but true. While there may be a driving technique that can make better use of this throttle mapping, it seems for most people, it only hurts fuel economy.

 

More than likely, your calculations over a single tank are less precise than the onboard computer due to differences in how full your fill-up was. Averaging over many fill-ups, manual calculations will be a little more accurate; but for a single tank, the variability of the filling procedure can cause fairly significant errors.

My experience with my '12 is that the computer is maybe a little bit optimistic on average, perhaps 0.5 to 1 mpg.

 

It bothers me that Honda is very vague about precisely what that ECON button does. It makes it seem more a gimmick than a feature.

 

Welcome to a normal experience driving a pre-2015 Fit! So that really defines what the Eco button actually is- with it on you're driving a 1st and 2nd gen Fit, and with it off you're driving a 3rd gen Fit! I find the best Eco button is my foot. When I use it responsibly, I get better gas mileage. That, and highway driving boosts the numbers considerably. City and suburb stop and go or short hopping will kill your numbers right quick. If and when I get a 3rd gen, I would probably use the Econ mode coming home from work in the wee hours of the morning when I'm driving relaxed and no one is behind me pushing me along.

 

Had the 2013 Civic with Econ and most on their forum mentioned it did not work around town, but got better results with it on longer highway driving. Its a gimmick to me, so I stopped using it with the Civic after testing it out with econ and no econ around town.

 

I've been alternating ECON off and on, and virtually all my driving is suburban stop and go with a little slightly faster sections here and there.


I definitely get better results with ECON on, at least according to the computer. And it's a sizeable difference; as much as 5 mpg, but usually closer to 3 per trip.


Just today I got 39 going one hour, and 35 back with ECON on and off, respectively.

 

I never used the econ button on mine yet, but I noticed when I fill up, I'm getting a range of around 385 miles give or take based on range in the trip computer. By the end of fuel running empty, the trip computer says I drove anywhere from 249 to 285. That is like 100 + miles lower than what it showed when I filled up. Why is that? How many miles are you guys driving on a full tank?

 

I've found the my gas light goes on and it still takes 1-2 gallons...I'm only putting about 8 gallons into a 10ish gallon tank- that's why your numbers are off.

 

Is this response to me? If it is, what do you mean my numbers are off? I'm filling it up all the way, about around 9 gallons. How many miles are you driving on a full tank?

 

Yes. Not sure what I'm getting on a full tank.

I fill up when the light goes on, and usually put in about 8 gallons. I'm getting about 40mpg. You said roughly 385 to 285, which is a delta of about 100. Our tanks are a bit over ten gallons. The 10+ gallon tank minus the 8 means there is still 2 gallons and change in the car. At about 40mpg the 2 gallons and change will give you the +/- 100 miles you are talking about.