Difference Between Normal And Eco Modes

[Aeneas]

I have looked at the manual but I am afraid I'm still not clear about the difference between "normal" and "eco mode" when driving a Prius. As far as I can see there is no reference to "normal" mode in the manual, although I notice it is used in several posts on these forums. I take it that people use the phrase "normal mode" to indicate when none of the buttons for "power", "eco" or "ev" has been switched on. If I am correct about this it appears that there are four modes on the Prius Gen III: normal, power, eco, and ev. The "power" and "ev" modes are, I think, easy to understand. In the power mode the car operates like a normal 1.8 litre petrol vehicle. In the "ev" mode it is essentially an electric car. In the normal mode (ie when none of the three mode buttons is switched on) I assume that the computer will determine the best combination of modes for fuel economy and the eco indicator light will show when the car is being driven in an environmental friendly manner. So what distinguishes this from the "eco mode"?

[Jan&tone]

Aneas, I think you are basically correct. My understanding is that Eco mode cuts pretty much everything by 30 percent thereby giving greater economy. However, this mode is only really effective in heavy traffic although I personally would use ev if the traffic was that bad. Others may have differing ideas as let's face it, we all drive a Prius differently!

[r04drunner1]

Yep, the "four modes" sounds about right.

"PWR = normal", I would quibble about as it's an Atkinson cycle 1.8 litre engine, which means it is less powerful than a normal petrol engine, but on the other hand it has an electric motor to add oomph!

Toyota reckon it's equivalent to a normal 2 litre petrol, I think that's very slightly optimistic to be honest but pretty close.

Where in Ireland are you located Aeneas? I am in Carrickfergus.

R04drunner1

[Aeneas]

Thanks for the replies. But I'm still not clear on the difference, if any, between "normal" and "eco" modes. On a recent trip to France I drove 1200 miles on normal (ie none of the three "pwr", "eco" or "ev" buttons was switched on at any point). With three of us in total and our luggage the car achieved 61mpg over the 1200 miles. Is it the case that if I drove on "eco" I would have achieved even higher mpg? And if so what is the essential difference between the "normal" and "eco" modes? As far as I can see the manual is not clear on this but if it is could someone give me the reference?

Another point in reply to r04drunner1 above: I don't think that most posters use normal to mean "pwr" mode although it is true to say that power mode gives the closest driving experience to a normal car. What they seem to mean by "normal" is driving the Prius with none of the three driving mode buttons switched on, and that is the sense in which I use it in the post above. Hope this is clear; and that someone can tell me the difference between driving with the driving mode buttons switched off and driving with the "eco" button switched on.

[beazee]

And if so what is the essential difference between the normal and eco modes?

From what I've read here or on Priuschat it's just the behaviour setting of the accelerator pedal. ECO mode is not as nippy, you have to press the accelerator harder, deeper to gain speed as in NORMAL mode.

[Grumpy Cabbie]

And you will find that in eco mode the car will ever so slightly hold itself within electric beford switching on the engine and then when the engine is running it again seems to hold it below the red power band longer. Guess its all down to accelerator programming but I do find eco mode makes a big difference in town traffic due to the above. Sometimes in normal you might just over press the accelerator and the engine switches on, only to switch off 1 second later when you slow up. In eco the accelerator programming is duller or less reactive and therefore the engine is less likely to fire up and as such more fuel is saved.

Also, eco mode adjusts the warm up cycle so that the engine will shut off more often when cold. Again saving fuel. It also restricts heating and a/c levels to save fuel too. You will probably only notice this in summer when the a/c is on quite high on the Auto setting - select eco mode and the a/c fan speed will drop to just two bars.

To bore you a bit more about eco mode, you'll find that despite the accelerator mapping being less reactive, it will still provide full power if you floor it! It's just the gentle presses of the accelerator that are dulled.

Hope this helps.

[r04drunner1]

Another point in reply to r04drunner1 above: I don't think that most posters use normal to mean "pwr" mode although it is true to say that power mode gives the closest driving experience to a normal car.

That's OK Aeneas, when I said "PWR = normal" I was quoting you, your full original quote was:

In the power mode the car operates like a normal 1.8 litre petrol vehicle

(emphasis mine)

I meant "normal" as in "normal 1.8 litre petrol" not "normal" as in "'normal' mode"...! Sorry for confusing things by abbreviating the quote, I can quite see how that confusion came about! And, yes, I am clear as to the difference between PWR and NORMAL.

I think Grumpy Cabbie has posted the best explanation I have yet seen on the 'Net about ECO mode. The only small detail I would add is that when you press ECO mode the multi-information display shifts to the Hybrid System Indicator (HSI). I personally find that rather annoying as I have the HSI already displayed on the Head Up Display (HUD) and I would prefer the multi-information display to stay exactly as I had already selected it!

I note that the Toyota blog site says:

"Using this mode, and keeping your driving within the optimum level shown on the Eco Drive Monitor read-out, can help reduce fuel consumption by 10-15%."

That seems a bit optimistic if you are already a light footed driver who uses NORMAL mode but also keeps driving within the "optimum level"... still, there's a nice writup on this site which summarise it all: http://www.prius3.com/specs/four-driving-modes

R04drunner1

[Aeneas]

Thanks for the replies. I think I'm beginning to understand the difference between the various driving modes. The manual is not very clear on all this though, as far as I can see. In general I find eco a bit unresponsive and so prefer the normal mode. And if I can get 60/61 mpg regularly with that I will be happy.

[Jan&tone]

Thanks for the replies. I think I'm beginning to understand the difference between the various driving modes. The manual is not very clear on all this though, as far as I can see. In general I find eco a bit unresponsive and so prefer the normal mode. And if I can get 60/61 mpg regularly with that I will be happy.

This has been an interesting topic for me, as i've had my gen3 a week now (and still loving it)

The last sentence is really interesting though - are we happy with the mpg that we get, or are we, by simple virtue of buying a hybrid, always going to be striving to get more and more mpg from our vehicles?

[r04drunner1]

The last sentence is really interesting though - are we happy with the mpg that we get, or are we, by simple virtue of buying a hybrid, always going to be striving to get more and more mpg from our vehicles?

I am well pleased with what I have been getting already without really trying. Strange as it may seem, I did not buy the Prius to get maximum MPG, if that were the case then I would probably have been better off with a small diesel.

The MPG in the Prius has been impressive. In my last car, a diesel Jaguar S-Type, I was averaging 31 mpg between fill-ups on a mix of town (very local, very short journeys <5 miles a time) and city rush hour (local, short journeys <20 miles a time). Best average consumption I saw was 50 mpg on the one time when I did a long trip at low speed (1 hour driving at 50 mph, on a motorway).

In the Prius, without really trying, I am getting just over 50mpg now in town (very local, very short journeys). I have been travelling less to the city (just two trips since I got the Prius) and I have not done any long trips at all.

Virtually all the time has been spent in NORMAL mode, with the odd dab into PWR or EV. EV is fun and it's frustrating that the car does not allow me to use it more e.g. when starting up on a reasonably warm morning, when I am not too bothered about the car heating up but I would like to drive out of our street silently. I have used ECO mode a little but found it frustrating to be honest. As an IAM member I am used to pressing on and don't like dawdling.

I have not tried advanced techniques like 'pulse and glide' or 'warp stealth'. I've read up about them and I think I understand the concepts, trying them out would be the next challenge. I suppose curiousity at some point will impell me to try some sort of hypermiling using the above techniques (note: where traffic conditions permit!) and it would be fun to get some high headline MPG figures for bragging rights.

But as to getting obsessed with MPG... nah, don't think so.

Having said that, the Prius does actively encourage striving for high MPG so you never know I might get bitten by the bug...! :P

R04drunner1

[Aeneas]

Thanks for the replies. I think I'm beginning to understand the difference between the various driving modes. The manual is not very clear on all this though, as far as I can see. In general I find eco a bit unresponsive and so prefer the normal mode. And if I can get 60/61 mpg regularly with that I will be happy.

This has been an interesting topic for me, as i've had my gen3 a week now (and still loving it)

The last sentence is really interesting though - are we happy with the mpg that we get, or are we, by simple virtue of buying a hybrid, always going to be striving to get more and more mpg from our vehicles?

Well the best we can hope to get is the manufacturer's public figure of about 72mpg. But that it derived from controlled conditions and not from actual everyday driving. I would hope to improve on my fuel economy, but realistically I don't expect to do much better than 60/61 mpg in normal everday use - and probably a bit less. I also suspect that as new users we focus on mpg a bit but this will wear off as we get used to the vehicle. My guess is that as long as consumption stays within a reasonable range most users will be content.

[Jan&tone]

I wonder what the record is for a gen3 Prius under normal everyday driving conditions? I'd imagine it would depend on so many variables that it would be impossible to quantify...

Ithink that anything between 60/68 would be satisfying, especially as we don't pay any road tax at the moment!!

[Sagitar]

Thanks for the replies. I think I'm beginning to understand the difference between the various driving modes. The manual is not very clear on all this though, as far as I can see. In general I find eco a bit unresponsive and so prefer the normal mode. And if I can get 60/61 mpg regularly with that I will be happy.

This has been an interesting topic for me, as i've had my gen3 a week now (and still loving it)

The last sentence is really interesting though - are we happy with the mpg that we get, or are we, by simple virtue of buying a hybrid, always going to be striving to get more and more mpg from our vehicles?

Well the best we can hope to get is the manufacturer's public figure of about 72mpg. But that it derived from controlled conditions and not from actual everyday driving. I would hope to improve on my fuel economy, but realistically I don't expect to do much better than 60/61 mpg in normal everday use - and probably a bit less. I also suspect that as new users we focus on mpg a bit but this will wear off as we get used to the vehicle. My guess is that as long as consumption stays within a reasonable range most users will be content.

Sorry, I made a pigs-ear of replying. Please see below.

[Sagitar]

If you look at the overall averages on Fuelly they tell you that around 55 m.p.g (Imperial) is what most people will get. It will vary from tank to tank for various reasons, but over the longer term, 55 m.p.g. looks about right.

I have just come back from a holiday in the Lakes. We drove one day from Ambleside to Keswick. The run down into Keswick is a long steep hill and when we reached the bottom of it, my traction Battery was full to the brim - not a sight you see very often. Just around the corner was a filling station where I bought petrol. I re-set the trip and drove to our hotel (about five miles) in slow moving traffic. When we got to the hotel, the tank average indication was showing 99.9 m.p.g. - I guess because of the very full state of the traction Battery when I filled up. I don't expect to see that very often either . . . . .

[Jan&tone]

If you look at the overall averages on Fuelly they tell you that around 55 m.p.g (Imperial) is what most people will get. It will vary from tank to tank for various reasons, but over the longer term, 55 m.p.g. looks about right.

I have just come back from a holiday in the Lakes. We drove one day from Ambleside to Keswick. The run down into Keswick is a long steep hill and when we reached the bottom of it, my traction battery was full to the brim - not a sight you see very often. Just around the corner was a filling station where I bought petrol. I re-set the trip and drove to our hotel (about five miles) in slow moving traffic. When we got to the hotel, the tank average indication was showing 99.9 m.p.g. - I guess because of the very full state of the traction battery when I filled up. I don't expect to see that very often either . . . . .

An I'll bet you didn't take a picture of it either

[Sagitar]

If you look at the overall averages on Fuelly they tell you that around 55 m.p.g (Imperial) is what most people will get. It will vary from tank to tank for various reasons, but over the longer term, 55 m.p.g. looks about right.

I have just come back from a holiday in the Lakes. We drove one day from Ambleside to Keswick. The run down into Keswick is a long steep hill and when we reached the bottom of it, my traction battery was full to the brim - not a sight you see very often. Just around the corner was a filling station where I bought petrol. I re-set the trip and drove to our hotel (about five miles) in slow moving traffic. When we got to the hotel, the tank average indication was showing 99.9 m.p.g. - I guess because of the very full state of the traction battery when I filled up. I don't expect to see that very often either . . . . .

An I'll bet you didn't take a picture of it either

It didn't strike me as that important at the time. However, I expect to be up there again soon and I'll see if it's repeatable and make sure I have a camera handy . . . . .

[r04drunner1]

When we got to the hotel, the tank average indication was showing 99.9 m.p.g. - I guess because of the very full state of the traction battery when I filled up. I don't expect to see that very often either . . . . .

Awesome!

Yeah, I suspect the 72+ MPG on the official tests was achieved with a VERY fully charged Battery at the kick off!

And with the car heated up to full operating temperature, a/c off and cabin heater off.

And (to bring this back on topic) running under ECO mode, with some EV thrown in.

R04drunner1

[Grumpy Cabbie]

When we got to the hotel, the tank average indication was showing 99.9 m.p.g. - I guess because of the very full state of the traction battery when I filled up. I don't expect to see that very often either . . . . .

Awesome!

Yeah, I suspect the 72+ MPG on the official tests was achieved with a VERY fully charged Battery at the kick off!

And with the car heated up to full operating temperature, a/c off and cabin heater off.

And (to bring this back on topic) running under ECO mode, with some EV thrown in.

R04drunner1

Nah, you can get 75 mpg easily on a steady run on the flat. I've done trips between Harrogate and York station and back and averaged 75 mpg for the whole trip and many of the 5 minute intervals showing the average of 80 mpg, 90 mpg and even 100 mpg and those are with the a/c on.

Hills however, kill the mpg's :(

[Seamaster73]

To those who whinge that the published mpg isn't achievable in the real world, remember you get tax breaks etc based on published emissions that aren't achievable in the real world either!

[kithmo]

EV is fun and it's frustrating that the car does not allow me to use it more e.g. when starting up on a reasonably warm morning, when I am not too bothered about the car heating up but I would like to drive out of our street silently.

R04drunner1

You need to make sure the heating is off and press the EV button within 12 seconds after the "READY" appears on the screen when you start up.

I do this and if the traction Battery has 4 bars or more and I don't exceed 19mph on a cold engine or 25mph on a hot engine, I can easily get off the estate (around 0.5 miles) in EV mode before the engine cuts in.

[r04drunner1]

Cheers Cabby, I got 64MPG today in ECO mode on a slightly longer trip involving a variety of roads / traffic conditions including a very short blast up the M/Way at 70 mph and quite a bit of stop/start heavy traffic. At one point the car was showing 80MPG for the trip, so yes I can quite believe 72MPG is achievable in the real world.

@Percy thanks for the tip, I must try EV on quickly, heating off and 19MPH maximum. It doesn't help that I have to take the car up a steep driveway at the start of my journey, however I have found that if I keep the speed at < 3MPH on that driveway then the petrol engine does not fire up.

[Grumpy Cabbie]

And I've found the Prius (and the Auris HSD is pretty much the same car) didn't start to achieve better mpg's until it had about 15k miles on it and it seems to be getting even better now after about 25k miles.

The more it gets run in, the better it seems to get.

[Aeneas]

To those who whinge that the published mpg isn't achievable in the real world, remember you get tax breaks etc based on published emissions that aren't achievable in the real world either!

Correct! And that's why I bought a Prius - to keep motoring costs down. Moreover, manufacturers' published figures do at least give a basis for comparing cars based on equivalent tests. But for those interested in fuel economy pointing out that it is difficult, if not impossible, to achieve manufacturers' figures in everyday driving is not whinging - it's simply a fact. I wonder how many disappointed Prius drivers there are who find that the 72mpg they thought they would get turns out to be 55mpg?

[Jan&tone]

To those who whinge that the published mpg isn't achievable in the real world, remember you get tax breaks etc based on published emissions that aren't achievable in the real world either!

Correct! And that's why I bought a Prius - to keep motoring costs down. Moreover, manufacturers' published figures do at least give a basis for comparing cars based on equivalent tests. But for those interested in fuel economy pointing out that it is difficult, if not impossible, to achieve manufacturers' figures in everyday driving is not whinging - it's simply a fact. I wonder how many disappointed Prius drivers there are who find that the 72mpg they thought they would get turns out to be 55mpg?

The day I collected my Gen2 in 2008, I went from home to Folkestone in it on my own with a full tank of petrol to start - A13/M25(Dartford Bridge)M25/M20 - returned 55mpg and I thought that was pretty good. It crept up to 61mpg over the next two years or so.

I've had my Gen3 for just over a week, 120 miles on the clock and tomorrow I'll be doing the same trip. I already have 58mpg on the display, but I'm intending to set trip b recorder to 0 before I go. It will be interesting to see what the display reads when I get to Folkestone.... If it's good enuf, I'll post the result on here If it's not then I'll quietly hide in the corner

[Doesn'tExist]

There really is no need to drive in ECO all the time, do as the manual states and just use it in heavy traffic (that is assuming ofcourse that the rest of your journey wasn't stop start ). Today, my normal commute from Whipsnade to Farnborough, use my PWR button to get across the busy road from our little lane, 'NORMAL' everywhere else hills across the chilterns, 80mph on the motorway, ECO on the M25 western roadworks...And I got easily without driving slowly 74mpg (on the computer)...

Driving in ECO would do my head in with the slow responses and it really doesn't do anything for faster driving. It just helps with the throttle responses to not 'rev' to much when pressing the pedal to move, keeps the engine to the left of the line.