Why there is default re-gen while coasting in "D" pure EV mode

Any driver who has driven any other vehicle expects it.

 

"engine drag" when you lift off the gas is normal for 'torque converter' automatic transmissions and pronounced in manual transmissions. Together they represent 99.5% [made up statistic] of the transmissions on the American road. If the Prius acted differently, any driver of any previous car would have to relearn how to drive. Toyota (legal team) values presenting the same driving experience drivers are used to. (so they don't crash into the car in front of them and sue Toyota)

As you note, there is no technical reason.

 

Expects a significant slow down when removing all pressure from the accelerator If the Prius went into a true 'neutral glide' it would feel odd to someone not expecting it.

It might be nice if they could make that a settable option, but that might cause more confusion.

 

Let me see if I can through some light on it:

	transmission gear	2017 Prime	2014 BMW i3-REx
1	N	maximum coast range	maximum coast range
2	D	lowest regeneration	maximum regeneration
3	B	medium regeneration	does not exist
4	dynamic cruise control	down to 28 mph	down to 20 mph
5	"foot fiddling"	claims near perpetual motion (*)	BRUHAAAAAA!

Bob Wilson

* - Three year old child on a "big wheel" tricycle comes to mind.

 

DRCC on the Prime takes you down to a full stop. (or is that only for the higher trim levels?)

 

but prius regen is much stronger in glide than a standard tranny. they could probably cut it by 50%.

 

That sucks.

 

but that reprogramming maybe part/all of the increased mpg's from gen 2 to gen 3. which helps all the prius drivers who don't read priuschat.

 

Much of the efficiency improvements came from improving the engine and running it at its efficient point whenever possible.

 

That depends on the car. In my 1972 Buick Skylark GS letting off the gas pedal was about like B-mode is in my Prime.

 

I've been using "N" since we got our first, 2003 Prius, and never stopped. The earlier versions had speed limits so you had to be careful going down hill with the engine off. Otherwise, it works just fine.

Bob Wilson

 

I used "N" on my 99 Solara and my 2012 v to great advantage but, in the beginning, I fooled with it in the Prime and found a combo of "B" in EV and long coasting in "D" to a stop were better than "N". Going down hill in EV mode, even on a slight down hill, will increase EV miles. Even in HV mode, using the HV portion of the battery, which replenishes better than the older Prii, is better than "N". My take is that "N" in the Prime is not does not give an advantage. Using the HV portion of the battery when there is no EV miles left is the greatest lift to mpg's. I find that any decline in the road will allow you you to use the HV portion of the battery. I use the DRCC and if there is a slight decline, I will pause It and immediately turn it back on. This should use the battery. Basically in HV mode your foot on the peddle determines if you use the battery or the ICE.