See below. Should we conduct a controlled poll? This is an outgrowth of my thinking about the latest episode involving the Prius and the CHP car which coached it to a stop, as well as numerous other posts spread over many threads. The varying comments from posts indicate seem to indicate that most drivers who try it say that the later Gen II Prius's have a throttle override, while some test their cars and find it doesn't work. Just speculation, but could there be actual differences between the Gen II cars -- such that for some the throttle override doesn't work [in the model years which should have it]? Might this be worth setting up a poll for? The prerequisite for voting in the poll would be that the driver has gone out in their car and tried it at speeds and conditions dictated by the poll, which would include (perhaps) on a highway, at a low traffic time of day, and that there is no traffic in sight? The directions would also, of course, clearly lay out what to do if the throttle override doesn't work. This board has so many members that given a decent polling response, it could achieve statistical significance, differentiating it from just a bunch of data which have no predictive ability. It's just possible that this could generate reliable information useful to Toyota, NHTSA, or Prius drivers, depending on how the results come out. (and let the chips fall where they may)
I would be willing to help, as long as "highway" includes two-lane state highway. I have to drive an hour and a half to get to divided interstate highway. I'm not willing to drive three hours round trip for a poll. Tom
I drive the interstate daily to work. THis throttle over ride you speak of-- you mean putting the shifter in neutral, or pushing the "P" park button, or pushing in the Power button? or something different?
Oh, c'mon. You don't need a massive poll to do this, I know how it works. I did a little confirmation experiment this evening, in fact, watching my pressure monitors to determine if the physical brakes were coming on, how hard, etc. [Yup, as much as I say "learn to drive your vehicle", five years and I'm *still* learning how to drive mine.] . First of all, if you are into the go-pedal at all, there's no regen. Not even part of the equation, as regen *only* happens near the very bottom of the pedal. [Where "bottom" == no foot on it]. So forget about any regen braking if your foot is asking for motive power. . If you left-foot the brake pedal, pressure goes to the hydraulics and you begin dragging the brakes. Guess what, this is how Chumpus in SoCal burned his brakes while still going at high speed! I bet he figured out how to do this, to make it look like he'd been trying to brake. Even with light pressure there are still plenty of kilowatts being dissipated in the brake parts, so of course they'll get nice and hot after 30 miles. And that drain of power likely won't let you reach full speed on an open road, but rather hold the car back to, oh, say about 90 MPH. Funny that. So here we are, lightly pushing both pedals at once and still moving. Doesn't matter if the engine is on or not, either, we could be doing this entirely in EV if the demand is light enough. Motive demand is motive demand, period. . Increasing the brake pressure past a certain defined point, measured by the master cylinder pressure sensor, triggers the hybrid controller to remove all motive power. Boom. It's rather sudden, and now those dragging brakes with increased pressure have a more profound effect on the car. Your pizza flies off the seat. Just like Carolyn showed us in the videos. Let up on the brake a bit, and motive power returns. Thus, the "override" requires braking like you mean it, i.e. you want to stop. . You can test where that point is at a standstill. While holding the brake, put the car in Drive, and then play with brake pressure. At a certain point you will feel in your butt-dyno where the motor cuts off the creep force or lets it return. That's the same pressure point, where driving force is simply disabled regardless of where the go-pedal is. It is *not* related to the point at which the brake lights go on -- that happens much earlier and is controlled by the plunger switch on the pedal assembly at the start of the stroke. . Simple enough?? . Interesting subtlety: if you've brought in some brake pressure and then let *off* the go-pedal, hoping it will switch back to pure regen, it doesn't. You have to get off the brake pedal and reapply, and then regen is brought in. So if you're one of those two-foot drivers, get out of the habit. . _H*
