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Discussion Starter #1
The electric motor is biased "ON" just a bit to provide the "NORMAL" tendency found in traditional cars with autopmatic transmissions to CREEP FORWARD just a bit.

If you stop your Prius o a bit of an upward incline it is likely that it will not roll backward. This is like the "HILL HOLD" feature found on some other cars. The Prius doesn't roll backward because the electric motor is holding the car and expends battery power to do so. Under these conditions note the energy display and you'll see that the electric motor is powering the wheels. If you put your foot on the brake the motor shuts off.

Not a giant savings but if you spend much time stopped on hills it could save some battery power to use your brakes. Some drivers with automatics use their accelerator pedal to hold their car on a hill by engine power. In a Prius this would waste electrical energy.

:D Pat :D
 

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I've observed that as well, but when I've been stopped on an otherwise level stretch of road. Maybe I'm light enough on the brake to register that, but not light enough to move forward? Better "light foot" than "lead foot" anyway. 8)
 

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Pat's point is that when you're stopped, with your foot on the brake pedal, "lead foot" is better than "light foot". It's not a lot of power (about 700 watts), but why waste the energy unnecessarily.
 

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Discussion Starter #5
Rsnyder, Exactly! They turn off the ICE when you stop for economy, so why "run" the electric motor. A programming "patch" to "kill the creep" should have no downside (that I can think of.)

Simulating "regular" cars is OK to a point and makes the car feel the same as all the rest but it isn't the same as all the rest. I don't thnk the slight regen braking that simulates a regular car's compressive braking is a good thing ALL THE TIME and could profitably be switched on and off under driver control.

:D Pat :D
 

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If you let off the brake on level ground, your prius will creep up to a speed of 5-15 mph (i've not tested it, so I don't know the exact value) ... idle speed.

What you are seeing is the operation of the engine/brakes to cover all the speeds between 0 and idle speed. It would really suck if your only choices were say 0 and 10, and you were trying to line up the car on a lift, or at a car wash.
 

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Discussion Starter #7
melgish, There wouldn't be a MISSING speed or power range as the foot throttle control would give you smooth control from zero power/zero speed up to full power/full speed. The "preset" creep simulates a regular car. I am not adamant that this "feature" be removed. All you have to do to have the computer switch off the "creep" power is to be stopped and plant your foot on the brake. What I suggest is that some of us might like to be able to turn it off or have it selectable (likewise the regen braking bias when "coasting".)

I think I underestand your objection and if that is the way it worked I'd never want it and it would be dangerous but I don't think it would work that way.

:D Pat :D
 

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The problem with using the accelerator pedal to control 'creep up to idle speed' is the car in front of you at the traffic light, and the exchange of information that occurs if you press to hard and your prius lurches forward.

You really do want your foot over the brake...
 

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Discussion Starter #9
I'm sorry, I didn't mean to belittle your ability due to some physical impairment. For the majority of drivers with normal motor control there isn't a problem. Many of us have two working feet and can "guard" the brake with either foot. :D

:D :D Pat :D
 

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patrickg said:
Many of us have two working feet and can "guard" the brake with either foot.
But some of us learned differently. I don't think I have hit the brake with my left foot in twenty years. My left foot is for the clutch or nothing.
 

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SkipHuffman said:
patrickg said:
Many of us have two working feet and can "guard" the brake with either foot.
But some of us learned differently. I don't think I have hit the brake with my left foot in twenty years. My left foot is for the clutch or nothing.
Yah, if I hit the break with my left foot, it would be as if I were pressing a clutch and the car would come skidding to a stop! :) Besides, it bugs me when I see someone excellerate while their break lights are on. I know I can not rely on that persons break lights to let me know if they are stopping or not.

I do agree that it is nice to be able to remove your foot from the brake and have your car inch forward. Having a swich might be nice for some people, but how practical is it? Do you load your Prius with a bunch of overrides so you can choose which features of your car you want to work like other cars and which features you want to change?

Maybe Toyota should expand their options so these kind of things can be added if someone wishes to have them. Like the EV button!!! Why on some cars but not all cars?

<stepping off soap box now>
Steve
 

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Discussion Starter #12
I can brake with either foot. Maybe I'm ambifootress. I can drive a stick or auto. My dad nearly threw me through the wind shield when he hit the power clutch. Power brake some fool put in the car where the clutch oughta be.

Lotsa cars have selectable all sorts of things and some remember which set of options goes with which driver. Suspension, shifting, mirrors, seat etc.

:D Pat :D
 

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I think we're still a few years away from 'skinnable' dashboards and control systems...
 

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i think the creep is very desirable and wouldnt have it any other way. also you should NEVER use your left foot for braking purposes.

and dont think if you stop on an incline that you will not roll backwards because i can say from frequent experience that if the incline is steep enough you most definitely will roll backwards.

there are many many streets where i live where you must keep your foot on the brake or you will roll back, even in drive.
 

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DaveinOlyWA said:
i think the creep is very desirable and wouldnt have it any other way. also you should NEVER use your left foot for braking purposes.

and dont think if you stop on an incline that you will not roll backwards because i can say from frequent experience that if the incline is steep enough you most definitely will roll backwards.

there are many many streets where i live where you must keep your foot on the brake or you will roll back, even in drive.
I thought the Prius had 'anti-rollback', which I know at least one previous car of mine had, where it senses if you're creeping backwards, and applies slight gas (or, in the Prius, electric motor) to compensate until you're not creeping back anymore. Yet, when I tried it in the Prius, I rolled quite a ways before I decided to stop. Now I can't even find a reference to it on their website...
 

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maybe it does and it simply doesnt work on my car.
 

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hmm interesting...

so does that mean my car should be looked at?
i dont know how far back the car will roll as i dont let it for obvious reasons but i did let it roll back about 3-4 feet once just to see what it would do.

now im gonna have to go out and try it again.
 
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