ECO vs Normal vs PWR Mode - really just accelerator mapping?

[pakitt]

I was wondering, based also on my driving experience so far with the Prius, if ECO, normal and PWR mode only affect the mapping of the response of the accelerator pedal. Let me explain.
In ECO mode, as mentioned on the user's manual, the AC effectiveness is reduced (less compressor used and lower fan).

These are my questions though - I think there is more than simply an accelerator mapping involved when selecting a mode. With the same acceleration applied (which means different pedal positions, obviously, in different modes, otherwise with the same pedal position one would have more acceleration in ECO and less in PWR), are the modes:
- affecting the amount of electricity going to the electric engine (more electricity in PWR mode)?
- affecting the charging/discharging patterns of the battery (e.g. tend to charge more in PWR mode to provide extra kick in acceleration, less in ECO mode, since acceleration will be on average lower)?
- changing the valves timing in the VVTi ICE engine (more gas in PWR mode, less gas in ECO), at the same acceleration requested (same bar length)?

Again, all this when asking the same acceleration. It comes without saying that if the pedal is pressed always the same, the 3 things above would change in any case, since the acceleration requested would be different in the same pedal position (accelerator different mapping).

BTW: in EV mode, ECO and PWR mode remain active - does this affect the acceleration pattern in EV mode as well?

[Jerry W]

As I understand it, there is no difference whatsoever between any of the modes, except in the amount of pedal pressure required to depress the accelerator a given amount...

[qbee42]

Eco mode throttles back on climate control. Other than that, the modes differ only through "throttle" mapping. At least that's how the Prius Chief Engineer explained it to us in Detroit.

Tom

[pakitt]

Originally Posted by qbee42

Eco mode throttles back on climate control. Other than that, the modes differ only through "throttle" mapping. At least that's how the Prius Chief Engineer explained it to us in Detroit.

Tom

Tom, if that is the truth, then the modes are not that much of help, apart maybe Eco mode, that actually does something.
I mean, if one learns to drive properly (read "economically") in power mode, then the other 2 are not necessary. If one learns how to get the PWR out of Eco mode, then PWR mode is useless. Then, keeping it normal is simply the best way?
I mean, I learned to use the gas pedal of my car over 7 years and got very good fuel consumption. If I have to learn 3 different ways of using the gas pedal with no added benefit, then I might just stick to 1 - normal and learn how to get power from it when I want and get ECO out of it, by being more feather weight on the pedal when I want to. ECO mode, with the A/C adjustment? this is, again, the only mode that has some value.
Then, why did they put the modes at all? since, e.g., to get PWR Mode you simply need to floor it??
I was hoping for a less simple reason behind the 3 modes.

[ManualOnly]

Originally Posted by pakitt

Then, why did they put the modes at all? since, e.g., to get PWR Mode you simply need to floor it??
I was hoping for a less simple reason behind the 3 modes.

For what I understand from previous posts, the 3 modes selection comes from concern for safety vs practical attainability in getting good FE based on average driver behavior.

Imagine one need to search for power-mode in the even of urgent overtaking or need for sudden power requirement.

The system will allow you to override the ECO mode with a simple near-WOT input on the accelerator.

And yes, I suspect one can still get good FE with driven correctly regardless in which mode one is in.

That principle of economical-sensible driving behavior applies to normal gasoline vehicles too.

[Rhino]

Originally Posted by pakitt

I was hoping for a less simple reason behind the 3 modes.

Its about fine motor control. Maybe you have it but other may not. Or other people don't want to spend one week adjusting to a car.

Why is the speeddial in a car so big - everyone can read? Why are there indicators about which gear (D, R, N etc) you are in - you shifted it didn't you? A reminder that the parking brake is set? You can feel it with your foot, no? If we can all type, why are letters printed on the keyboard?

It is ergonomics - to make it easy for all people.

[qbee42]

It's about fine motor control, and also about marketing. Having the three modes is fairly cheap and easy to do, and they add a certain gee whiz aspect. They also change the perceived peppiness of the car. Honda figured this out years ago: If you map most of the throttle response to the first bit of accelerator travel, it makes the car feel very powerful. When you drive a Honda Accord, you press the gas just a bit and the wheels spin. It makes it touchy to drive, but people like the feel. It doesn't make it any more powerful, but it feels more powerful.

The three modes let the Prius fit the expectations of a variety of owners. Those that are serious about mileage will like Eco. Those wanting something sporty will enjoy Power. The rest of us can drive around in Normal and do just fine.

Tom

[daveelt]

Here is my question, since all the buttons do is change the mapping of the accelerator pedal, why can we not get the eco indicator to come on in power mode.

The HSI is in the same spot in normal, press power mode button and leave the HSI in same position and eco indicator goes out.

Brake and go into CHG in HSI and the eco indicator does not come on in power mode. Have the instant MPG meter at 100 MPG, still no eco light????

Did they just disable the ECO light in power mode even though you are getting the same gas mileage as in other modes when the ECO light is on?

[qbee42]

Originally Posted by daveelt

Here is my question, since all the buttons do is change the mapping of the accelerator pedal, why can we not get the eco indicator to come on in power mode.

The HSI is in the same spot in normal, press power mode button and leave the HSI in same position and eco indicator goes out.

Brake and go into CHG in HSI and the eco indicator does not come on in power mode. Have the instant MPG meter at 100 MPG, still no eco light????

Did they just disable the ECO light in power mode even though you are getting the same gas mileage as in other modes when the ECO light is on?

The ECO light, like all indicators in the Prius, is driven by software. Someone made a decision to not use it in power mode. I suspect it is a deliberate attempt to move drivers away from power mode if they are interested in economy. Much of the success of the Prius comes from modifying the behavior of the driver with feedback.

Tom

[daveelt]

Kinda what I figured. Funny thing is, I find my eonomoy is often a little better in power mode than in normal. I think it is also a human behavior thing. I think when I drive, pulling away from a stop, I natuarally like a little pick up, so in non power modes I ened up pushing the accelerator much farther wearas in power mode, I get immediate response so I end up acctually using less HP!!!

Funny how that works both ways