What do the "power settings" actually do?

Great questions. This was explained in another thread; It was very interesting. I wish I could locate it.

My Three model jumps off the line quicker in Power Mode, (the accelerator pedal is more sensitive and "light") but then seems to resume normal performance (being GUTLESS.) Just kidding. Some guys in this forum drive all the time in Power mode. They swear by it.

I do get better gas mileage in Eco mode. But you have to mash down harder on the pedal to get some engine speed. I seem to recall a Toyota information sheet saying that the top speed and internal engine power do not change, regardless of which "driving mode" you are using. Hopefully the more knowledgeable folks will chime in here.

 

To my knowledge:

1) no
2) no

The modes make sure that the response to the pedal is more or less strong with the same movement of the pedal itself.
But the total amount of power available is always the same - if you floor the Prius in Eco or Power mode, the top speed and the 0-60mph-100km/h performance, is exactly the same (at least in Gen3).

But...:
1) in Eco mode, the A/C is used a bit differently to avoid using too much energy (therefore electricity), both in summer, and in winter (the ICE is used less to heat the air, as the AC fan is slower and the wind chill reduced);
2) in Power mode the ICE tends to be kept running more often to make sure the battery is charged more than in the other modes
3) there is speculation that Power mode will give access to 650V, rather than 500V, to the MG2 in more of the pedal range, rather than in ECO (where you really have to press hard to have full power available)

There is also a lot of psychological influence at work, when you select one mode or the other.
E.g. Power in city is so reactive, you seem to have a Porsche; Eco is a slouch after using Power.

Eco moreover allows a very fine tuning of the requested power for the first half of the pedal travel.
Toyota claims that in Gen4's Power mode, the car will learn also how you drive (steering wheel position, lateral g forces, etc) to have the engine run when in other modes it won't, to make sure the response is snappy when necessary (e.g. in winding roads). Whether this is true or not, only experience in the next months from Gen4 drivers will tell.
Moreover it is said that Eco mode of the Gen4, is equivalent to the Normal Mode of Gen3 - and I can say that is actually true, as I could experiment in my test drive.

Whether you have a good fuel consumption in any of the modes, it has a lot to do with how smooth you drive, and whether it is winter or not (see note above on how AC works in the different modes).
For example, Power mode in winter city traffic, and a heavy foot to the next red light: not a good idea. Power mode in city traffic, smooth driving (assuming you can control the foot so fine, as it would be possible in Eco), at 20C: best fuel consumption (likely like Eco mode).
Driving with Eco, Normal or Power mode at constant highway speeds, no real difference in fuel consumption.

 

Of course I'm talking Gen 3, but my understanding is no, Power and ECO modes do not change internal operation of the engine itself.
Only the interface and way the vehicle utilizes and interacts with the engine, primarily through accelerator pedal sensitivity re-mapping.

Is this correct?
On the Gen 3, Toyota has buttons for 3 modes, EV, Eco and Power, no button for "normal", normal is the 4th "mode" but designated and chosen by the pressing of NO button. No mode selected of the 3 buttons means you are in "Normal".

 

Excellent reply, pakitt. Now I understand much better. Thanks.

Electric Me, yes, my Gen4 "White Knight" has a button that you use to scroll through the 3 driving modes: Eco, Normal, Power, (and the screen changes colors for each.) And just to the right of the Mode button, there's a separate button that says "EV" on it. I haven't even tried it yet.

 

Thanks.
I did not know that about the Gen 4.
I suppose it's a good evolution as occasionally we get posts from new Gen 3 owners wondering "how" to get into normal mode, and have to explain that it's the "ghost" mode designated by really no designation.
So good move Toyota.

 

When I drive my MPG was the same in normal and eco. But when my wife drives with a heavy foot it makes a big difference. So I leave it in eco all the time.

 

I have nearly 4,000 miles in six weeks in my Gen 4 Three. I wonder if the rpm is kept generally higher in the ICE in the Power mode so it is instantly more responsive? We live in the Eco mode but occasionally play with other modes. I'll be watching how the heater works in Eco mode.

 

I don't think so, it's just that to accelerate up a hill for instance, or to get up to speed, you need to press the accelerator further. The final effect seems to be the same - sort of like the MERCEDES in the '60s where they had a long travel accelerator compared with most cars. MERCEDES drivers got used to it.

The ECO setting is easier to finely modulate the accelerator if you're playing "chase the most litres/100km" game.

The A/C settings are affected though, I believe - there were comments about the A/C working better when NOT in ECO. Not sure about the heater, though.

 

I have my A/C in Eco all the time and it work fine. I used power mode in the freeway did it for a month gas went up 10 dollar more. I think the Gen 3 was faster in power mode.

Posted via the PriusChat mobile app.

 

Up to a point, but if you make the pedal travel gross enough, it begins to work against you. It can be easier to control a small motion than a large one. I understand with fourth gen all the pedal travels were remapped to be somewhat quicker response, so a little hard to compare.

I do know with third gen 3 I quickly got tired of having to tromp the gas to get an adequate response. It was tedious delay, not helpful.

 

Other than the heating/cooling of the car interior the car works the same in each of the three modes. It's just that the accelerator pedal is "touchier" in power mode and less "touchy" in eco mode. Remember you are not opening the air control valve with your foot, you are just asking the computer to do so. The amount it opens vs the amount you press down is changed in the three modes. At closed throttle they are all the same and at open throttle they are all the same, as Pakitt stated.

This is a trick many car manufacturers use to make the customer think the car they are buying is very powerful. The power comes on fast at small throttle pedal depressions. This -should- be outlawed! It can be dangerous for the less experienced!

The other mode is EV. In this mode if the battery is not too hot or cold you can stop the engine from starting (for a few minutes or so and at low speeds). Nice for shuttling the car around the yard, out of or into the garage, etc. without having the engine start and go through the "cat warmup cycle".

 

I just wish EV mode was more reliable. It is so unpredictable (well, in 3rd gen) as to be useless. It's more-or-less guaranteed to NOT work with a stone cold engine, in my experience. And that's the one time I really could use it.

I resort to using the ~15 second EV window at startup that's always available. If it were 60 seconds it would make for a lot less shenanigins. With 15 seconds I can roll the car from the garage to the driveway. But if I need to get it right off the driveway, parked in the street (son coming over for oil change, for example), it takes me three starts-and-stops.

And push it too far, have the engine start up for just a few seconds, if I then shut down: I'm due for a shaking-at-start-up, the next morning.

 

The one thing I've noticed between eco and normal is the kick out for ev mode changes from 25 eco to 45 normal mph

 

a time window of ev would have been nice for the gen 4, so you could move a cold act around your property. maybe a minute or two under a certain speed. i guess toyota really isn't listening.

 

Would be nice on third gen too. The 10~15 seconds grace currently available at every start up (and EV via the button is nearly invariably a no-show) makes life "interesting" when you're doing the driveway shuffle.

(Hmm, harping on, see I said all this, up the page. Oh well.)

 

My wife's description: "PWR makes the car beat all the Implants from Texas in their giant lifted duelly super diesel stroke pickup trucks"
We live in Colorado.
When it snows - she says the same thing about our Subaru wagon.....just replace "PWR" with SNOW.

 

I think this graph explains the "drive modes"



Posted via the PriusChat mobile app.

 

I've been known to split that shuffle into two or three separate movements, shutting down and restarting between segments. But this has been only moderately successful at keeping the ICE shut down.