Driving in the ECO Mode?

in mountain driving, or foothills, im not getting much of a difference between eco and normal

almost seems better in normal. As you can boogy up the hills a little quicker before getting into power, then with just eco.

 

cruise control is something i rarely use because it's something a car sees as.. "OH.. I have to maintain this specific speed.. doing what i have to.."..

... meaning on those uphill runs.. the car is going to go into the red PWR zone to keep up and maintain that speed.

the main advantage of driving without cruise control is you have the ability to see what's upcoming in the road... so if you see that uphill ahead... you can compensate better by accelerating a bit to get to a higher speed, and then slow down/coast up and over the hill before you can let the car glide on the downhill portion.

if your commute is mostly flat... then i would use the cruise control if i was too lazy to deal with holding down the accelerator.

on uphills though, the car becomes a tad sluggish while in ECO mode... and less responsive to accelerate (which what that mode does).. causing the car to really, really slow down unless you floor the gas pedal a bit to make up for that insensitivity due to the car being in ECO mode.

i'm used to driving a lot.. and most times don't use cruise control at all.. even for extended trips... so could drive an entire 6-10 hr trip if i wanted to without using it...

but i suppose.. there might be a few minutes or so perhaps where i need to rest.. which i'll turn it on only for a slight bit until my leg was fine... and then turn it back off.

 

Unless the grade you're climbing is miles in length, and then it doesn't matter much in terms of MPG how you enter that climb.

 

i havent seen much difference between the two, but it might have to do with they way i drive.

 

EV mode is good if you are in a parking lot and about to park for a while. On startup your engine will be running for warm up anyway and will charge some of your battery back up.

 

I leave ECO mode on myself, the EV mode always kicks off when I start accelerating or states its not available or states my acceleration is to quick. so Im better off just accelerating slow enough to keep the gauge in the lower portion and it will stay in EV mode. most part I can still accelerate at the pace of traffic especially if its a slight down grade. And then you can get EV mode at 43 MPH or lower by letting off the gas and then maintain a gentle deceleration. Ive change my employment so I will get to do much more city driving now. once I get my car back from the body shop next Monday

 

I've been driving in ECO mode since I got the car. Three fill ups. With the last, I switched ECO off. By the dash, I'm getting better mileage. Figure I'll do three fill ups and see what the numbers say.

 

I have had my 2012 Prius for two years now and my experience has been that you get an extra few mpg by using ECO mode. Not much difference in the spring and fall, but in the winter and summer you really show a difference. I live in the Kansas City area with hot summers and cold winters. Last year I drove exclusively in power mode, but was a bit disappointed in my mileage variations during winter and summer. This year, I decided to try ECO mode exclusively and have noticed little difference between summer and winter which is a big help for us in the hot and cold climates of summer and winter where the battery is affected.

My averages (not as shown on the dash, but actually measured at the pump) are 50 mpg with about 1/3 city and 2/3 75 mph highway driving. I drive alot on the highway.

In power mode, my average was 46 mpg with the same city/highway driving makeup.

 

I just bought my '12 Prius C yesterday (love it!). I've been driving its Great-Grandma - the original model, '03 - for 9 yrs & 125K miles, very happily; now I'm letting my son "buy" it from me.

If anyone still on this thread wants more info about this topic, there are other threads with helpful content. "Eco vs. Power Mode" is a good one.

Anyhow... I'm still learning my way around the car and how it differs from my older Prius. But...

First of all, to whomever introduced EV mode into the discussion, NO!!! EV mode is driving on the battery only. (What the old Prius has as "B" gear.) It is only for emergencies and very slow short trips, such as in a parking lot. The car will override this selection at about 12 MPH, thankfully, or you'd be in major trouble. But DO NOT use this mode for regular driving.

As concerns the others, what I've come to understand - please tell me if I'm correct! - is that ECO mode is designed to use less A/C and better control the throttle. As for the A/C, that makes perfect sense. I would therefore turn it off if I wanted to cool the car in a hurry on a hot day, akin to using the "MAX" A/C setting on the older Prius. As for throttle, I've read several differing opinions. Most agree that if you need powerful acceleration (such as merging onto a hwy.), you should turn off ECO mode - and apparently the car will override and do this for you if you depress the accelerator as much as you naturally would in such a situation. Some folks report better MPG in ECO, some not - apparently depends on the hilliness of the terrain and the way the driver's foot engages the pedal.

My instinct would be to use ECO mode as the default, only turning it off for extra A/C and quick engine power. But I might try a couple of fill-ups each way, and compare the mpg I get. What do you all think? Please respond if there's something I should know - thanks!

 

Kitty,there is an advanced hypermiling technique that actually promoted the use of EV-only acceleration but it is an advanced technique and should only be used once you know what you are doing. The newer cars allow for much more use of EV than the older cars did. That being said, the c is an excellent t platform for hypermiling. If you know what you are doing, 65-75mpg tanks should be attainable.

 

I agree with the above.

The one unique thing ECO seems to do is change the air conditioning behavior a bit, with the aim to improve fuel economy. Other than that: I found the pedal response in ECO just too sluggish, and went back to "Normal" mode. Pedal response in "Normal" mode is no where near too touchy, it's about, well: normal.

 

You are probably getting better at driving the car, so if the 3 tanks at Normal mode are better, go back to ECO and see if things keep improving.

 

Agreed. There is a learning curve for driving each car efficiently AND with a brand new car you have to consider tire and mechanical break-in.

 

And 'most' would be wrong. And the car does NOT override the mode. It doesn't need to, as all the power is there available in ECO mode*, it just takes more pedal depression.


* - actually there might be MORE power available in ECO mode if the AC is on, since ECO mode uses less power for the AC, so more is available to accelerate.

 

I agree with Corwyn. Additionally, it takes longer to turn Power Mode on, allow it to "engage" then mash the gas pedal than it does to leave it in EcoMode and just floor the pedal.

 

This is just a quick graphic, my idea of how the throttle response varies. All three modes will give you "full" throttle. Kind of an oxymoron, it's actually completely "unthrottled", ie: wide open. Anyway, all I see ECO doing, at least regarding the gas pedal, is being more reluctant to respond to your requests.



(BTW, I like the new website's image insertion method: you no longer need to go through the labourious process of uploading the image to PriusChat gallery.)

Addendum, see someone else just posted a similar graphic. Oh well

 

That is only the case below half throttle or so. If you are traveling at say 55mph, then for a given amount of increased pedal depression, ECO mode will give MORE acceleration. Acceleration per pedal movement is given by the slope of the line. Normal mode is thus constant acceleration per pedal depression; Power mode is more acceleration per pedal depression in at low speeds, and less acceleration per pedal depression at high speeds; Eco mode is the opposite with less acceleration per pedal depression at low speeds, and more acceleration per pedal depression at high speeds.

If you are concerned about accelerating as fast as possible from a red light, be in power mode. If you are concerned about accelerating as fast a possible to merge on a highway (at speed), be in Eco mode.

 

I've found I just don't like ECO. I want to get moving, step on the pedal, it always seems to underestimate my request, and I need to push down further. Get's tiresome. I'm not sure who would benefit from the mode. It seems like you have to be more of a leadfoot in ECO, to get the response you want.

BTW, I agree regarding ECO accelerating more toward the bottom of pedal travel. It's miserly at the beginning, then playing catch up.

 

Hypermilers like to have more throttle control at low speeds. This is what Eco mode gives them.

'Leadfoot' is only a bad thing if it results in either more fuel usage, or physiological problems.

 

This is why I like Eco Mode. I need to have fine control of the throttle to keep engine load where I want it and to control engine on or off scenarios. In normal and especially power mode, a tiny bit of throttle inut causes you to blow right past these critical areas needed to maintain high mpg. For non-hypermilers power mode is just fine unless you run the A/C a lot.