keeping pwr mode on

Many of us spent a fair amount of time with the Prius chief engineer in Detroit during the 2010 Prius unveiling as invited guests of Toyota. We spent a lot of time quizzing him about the various modes.

Tom

 

That's not exactly, literally correct, except the flooring it part - all 3 modes give max power when floored.

None of the engineers have explained exactly all the differences between the modes when they are not floored, but it is true that the differences are "more noticable" in the first half of the pedal response.

 

Add me to the list...I don't always use PWR mode, but I do prefer it much of the time. I'd rather not have to hit the button every time I get in the car...

 

Correct. The throttle mapping response differences diminish after the first half of pedal travel. Full power is available in all modes, so if you mash the pedal you get the same thing in all modes.

As mentioned above, there are other differences: In Eco mode climate control is much less aggressive and ICE shutoff more aggressive; Pwr mode favors running the ICE and higher power settings.

Tom

 

I think the system now is very honest. The Prius is rated for around 50 mpg so the average drive should be in economy mode. That's because Prius drivers get privileges like HOV, better parking at malls (in my neighborhood) and etc.

If Toyota allows someone to push a button and drive the car for the next 10 years on power mode, then I will argue it is not really a 50 mpg car. Just a regular car with an EPA cheat mode for passing inspections and emissions and getting special privileges. A little barrier to power mode is the price for claiming a high mileage.

 

While I definitely agree on the need to prevent cheating on the EPA tests (which other manufacturers have attempted), PWR mode actually wouldn't change the numbers much - partly because the Gen III is nearly equally efficient in all modes, but mainly because the EPA testing regimen has strict controls on accelleration rates and whatnot so that the results wouldn't really change regardless of which mode was chosen.

That is not to say that there couldn't be some minor variations due to other settings unrelated to accelleration (such as cabin heat), but using the EPA regimen, PWR mode wouldn't change the 50mpg Prius to a 40mpg car - it doesn't even change it to a 48mpg car, it's more like changing an approximately 50mpg car to an approximately 50mpg car...

You have to accellerate much stronger than average to cause any significant mpg drop in the Gen III. And while PWR mode may make it easier to do that, Normal mode (or even ECO) doesn't exactly prevent it.

 

The Power mode not staying on is documented in the manual, it is therefore not a bug, but a design decision. Sure, they could have had any of the buttons (EV/Power) sticky between starts, they chose not to do that, and decided they would make ECO sticky. Unless you have the code to the ECU's, and a way to assemble it make changes, it isn't going to change. It is possible if enough people ask for this change, they could make it happen with a firmware upgrade, but that isn't too likely, unless other bugs are discovered, making the reprogramming of the ECU required (it costs them money to have a dealer do anything to the prius)


Mitch

 

Again I say: PWR mode doesn't waste fuel.

And if Toyota wanted us to be happy, they would have given us the CHOICE of making it sticky or not. (kinda like the backup beep...)

 

Well, that explains it.

Tom

 

I like your style.

Tom

 

It was missing the eye lids and lambo doors.

You should be happy that you have a PWR mode! The Iconic Prius generation didn't have one.

 

Tonight I had a 45 min drive in a mix of roads and traffic. I had fun switching between Econ, Normal, and Power as I encountered different situations...In my opinion this is the Prius equivalent of Paddle shifters on the steering wheel. Anticipating the correct mode to match the traffic situation.

It was kind of exhilarating...Perhaps too much so....I may need some therapy...