Driving style differences

We've had no sensation of unresponsive brakes, and Megan has had to slam them on a number of times driving to and from work on S. Western Ave in Chicago when people have cut in front of her and stopped to make a turn.

I mean, from the time we first test drove it, I was surprised, expecting something different. To me, it just drives like a car.

 

Yeah,

Can you describe your brake fade and when it happens?

This car do have regen braking and I don't see why that should "fade". I find the brakes very responsive and if you jam the pedal hard the friction brakes does it job remarkably well (even if you don't have a lot of play there).

I'm curious to what you feel and maybe you want to have your brakes checked?

 

Sounds like it's time to try out some handling upgrades. For a quick, relatively cheap upgrade, try out the BT Stiffening Plate. It'll noticeably improve cornering and ride stability. After other numerous upgrades, my Prius is very responsive now. I take it into the Cascades regularly to rip up some windy roads. VSC makes for some nice powerslides on some of those hard corners

 

I can relate somewhat to the points you make - I too am from 'across the pond' originally and while not having raced, spent many years in high-speed commuting (much like a race but without the Marshalls!) and on relatively narrow, twisty roads where connectivity was a crucial part of making the car work well and getting places in reasonable time.

In some ways, the experience you are getting may be due in part to the fact that while many of the systems in conventional cars are direct mechanical or hydraulic, those same systems on the Prius are largely electric. The result is a very different sense of 'feel' and, for example, in terms of the steering, rather less of a tactile sense of connection to the road. The Prius also suffers a little body roll, which reduces the seat-of-the-pants sensation of driving that is common in European (and many Japanese) cars.

The result is a degree of detachment that I can see might be disquieting when drawing on those experiential comparisons.

However, for me, I have not found the issue to be a problem in any way because when focussed on the job of piloting the car, I've found it easy to get feedback from the vehicle and road in other ways, such as using the feel of the body roll to determine good balance in cornering, aiming the vehicle at a point in the road and using a mix of steering, throttle and braking (if necessary) to get to the precise point, taking speed cues from external sources such a road noise and vibration rather than engine... and that's not to mention using the Energy Monitor display to continuously 'see' what the car is doing and participate in it doing it well.

I think it would be hard to accurately describe the Prius as 'engaging' to drive in the same way that, for example, a classic Mini always was, but it IS engaging on a different level, even if it requires the finding of different ways that the car communicates the driving experience.

That isn't to say, however, that brake fade is something you should be encountering. In a new car, you shouldn't experience that problem even after riding the brakes hard down a steep hill, and in the Prius with the engine braking 'gear' that's not something you'd typically need to do anyway. Alternatively, it may be that as suggested, you're feeling a variation in pedal pressure and inertia as physical braking effort blends or replaces regenerative braking.

 

<div class='quotetop'>QUOTE(dsam1961 @ Jun 8 2007, 09:07 AM) [snapback]458051[/snapback]</div>

As for brake fade, if you are noticing this "fade" occur around 6 or 7 mph that would be normal. At 6 or 7 mph regnerative braking cancels out and you go to all friction braking. This is because the regenerative system cannot supply enough precise resistance at such a low speed. This will feel like a lurch, or rather it feels like my old car automatically shifting into 1st in anticipation of coming to a stop.

Unless you panic stop, most braking is provided by electrical resistance, until you reach 6 or 7 mph. The electrical resistance is a fairly linear system. The more pressure you put on the pedal the more resistance the system applies. At some point the braking computers will add in friction braking if the demand from the pedal indicates braking need greater than what electrical resistance can provide. Brake pedal feel is entirely simulated. Danman is much better at describing the hydraulic simulation system which is supposed to provide hydraulic brake pedal feel. Honestly it does provide hydraulic feel, but it isn't the same is being directly connected with a master cylinder. If you are not a performance driver the difference is mostly unnoticable; press harder, more braking; car comes to a stop, good.

All Prii since MY 2004 have had electronic brake force distribution and panic braking assist. I don't drive like a wacko and don't find myself in too many emergency reaction situations, so I'm not sure if EBFD has ever been used. However I have felt the panic braking assist and it is very good. Antilock also works well, but very differently than other antilock systems I have used. I do not recall there being any brake pedal vibration when antilock is engaged. The stock Goodyear Integrity tires are terrible and on damp roads traction control will light up frequently. Annoying, but part of how the system works and is controlled. Better tires lead to less TRAC activation. Oh, and you cannot defeat traction control because that system also doubles as a control system to prevent hybrid drivetrain overrevving. If you get one tire spinning wildly out of control the items in the hybrid system are spinning with that wheel and without some system to keep that under control you might risk overspinning one or both of the motor/generators.

I suspect that you are missing the ability to modulate the brake pedal and as such minutely adjust hydraulic pressure to the brakes. I just don't think that is going to be possible in this car with the computer system managing the brakes.

Your issue with throttle response is much the same. This is a throttle by wire vehicle, but also, since it is a hybrid the computer is again in control. Like the brakes, the throttle is a user input device. The onboard systems receive input from this device and then translate those inputs into vehicle behavior. Pop the throttle and the car is going to light everything it has got to get you off the line. Ease into it and the systems will easy you away from a stop using the proper mix of electric and gas power, based upon its programming and that programming's response to your actions. Your behaviors toward the throttle and brake are commands to the computers to behave in certain ways. It is then up to the onboard logic to determine how to acomplish that goal.

As for engine speed, this is a non-factor with regard to driving this vehicle. The engine is going to do its own thing based upon what the computers are telling it to do. It may rev up/slow down, start up/shut down and without much connection to what you believe you are doing with the vehicle.

I do not wish to offend you or your sensibilities, but are you a pilot? I'm not, but am an aircraft and aerospace fan. I followed the development of the 777 many years ago and have kind of haphazzardly followed the development of the 787. I also keep my eye out for stuff that is going on at Airbus, but I'm not nearly as close to them as Boeing. Airbus is fly by wire, a good chunk of Boeing planes are also fly by wire, now. The difference. Airbus has used a joystick mounted on the left or right cabin panel, depending on the pilot's seat, right or left, that provides for manual aircraft flight control. The problem, there is no feedback. The 777 is also fly by wire, but utilizes a traditional yoke and also provides force feedback through its fly by wire system. Airbus pilots get used to not having feedback through their flight controls. Boeing pilots have typically flown aircraft that are cable controled as such they are directly connected to the conrol surfaces. They expect flight feedback. So, when Boeing introduced fly by wire in the 777 they made sure that their system looked and felt as much like a cable controlled system as they could. This meant including many sophistated system which could accuratly reproduce yoke feel based on control surface position and air resistance over those control surfaces. I bring this up because Toyota is trying to do the same thing with the Prius, but the difference is the ability to provide an accurate reproduction system in a vehicle that costs $25,000 rather than hundreds of millions of dollars.

I consider it remarkable what Toyota has done in what is a relatively short engineernig time span with regard to throttle by wire and brake by wire. I certainly hope you can mentally adjust to a different way of driving. The advantages of the technology used by Toyota are so overwhealming that frankly they have rewritten the book on vehicle design and development; so much so that in 10 or so years these technologies will probably be domant in the industry.

 

Since getting my Prius, I find myself more connected to the technical aspects of driving rather than the more enjoyable ones. I am more aware of the traffic around me, I am more anticipatory in my driving technique, I pulse and glide when I can, I stick to the speed limit and am more aware of my speed and the relationship it has to mileage, etc.

In my stick shift V-6 Jetta, I enjoyed much more the "fun" of driving -- downshifting into curves and accelerating out of them, coming up on someone's tail and then passing them in a blur, etc. Getting a Prius has TOTALLY changed my driving habits. My friends liken my Prius to a golf cart and me to an old granny LOL!

I'm glad I got the Prius, and am happy to have abandoned my previous driving style for something that I know is doing less to destroy the environment. With everything that's happening with global warming, I could not justify 22-25mpg for any stretch of road -- it actually pained me to know that I was being so wasteful when there was a much more economical, smarter, and more responsible alternative.

This brings to me to something slightly off topic... the Prius is NOT "good" for the environment, as I hear some people say on this forum and elsewhere. Driving a vehicle, period, will never be "good" for the environment -- rubber is released into the environment, heat reflecting and CO2 absorbing vegetation is destroyed and animal life displaced in favor of heat-retaining and environmentally poluting asphalt, and all commercially available vehicles consume fuel that is created at the expense of the natural environment and produce a byproduct that contributes to global warming. The Prius just destroys the environment more slowly than its less efficient counterparts.

This is why I find it a ridiculous argument for some to say "hey, you have a Prius now so go drive it more". That's like buying low calorie food just so you can eat more of it, when the purpose is to lose weight or live a healthier lifestyle. My Prius spends more time in the garage than my VW simply because the process of owning a Prius has made me hyperaware of the damage we are doing to our planet. There is no more important issue than global warming and the need for CO2 reduction -- our lives literally depend on it. The day each of us realizes that we need to start making sacrifices in order to help preserve a liveable planet for our children and grandchildren is the day we ascend to the next higher level of humanity.

Thanks for letting me get this out of my system.

 

<div class='quotetop'>QUOTE(dsam1961 @ Jun 8 2007, 09:07 AM) [snapback]458051[/snapback]</div>

You my friend are a jet pilot.
The Prius is a glider.
They both do the same basic thing, but are controlled in different ways and feel very different while doing so.

Is one safer that the other?
No, but they are both great fun in their own way.

You wanted practical. You just need to learn to enjoy operating a glider.

 

<div class='quotetop'>QUOTE(Sufferin' Prius Envy @ Jun 8 2007, 03:02 PM) [snapback]458316[/snapback]</div>

I wanted more, and that's what I got with the upgrades. Even gliders can get a handling boost with some chassis bracing. My car would be a good durability candidate. I really enjoy driving this baby hard, nowadays. There is a bit of a learning curve in working around some of safety features, and taking advantage of it.

 

<div class='quotetop'>QUOTE(efusco @ Jun 8 2007, 09:14 AM) [snapback]458057[/snapback]</div>

He lives in Bell Canyon.

Google Maps Satellite Image

 

<div class='quotetop'>QUOTE(Sufferin' Prius Envy @ Jun 8 2007, 03:02 PM) [snapback]458316[/snapback]</div>

I agree with Patrick. (Doesn't happen often. ) Your perception of a car is highly dependent on what you are used to. When I moved from my '89 Civic to my 2004 Prius, I felt that I was in a much faster, but slightly less responsive car. The brakes in the Prius required a much lighter touch. The Prius is an extremely consistent car, so once you become accustomed to it, it is very predictable.

But I understand your feeling, because for about three weeks now I've been driving Yevette (the EV e-'Vette) a ZAP Xebra SD, which has no power steering or power brakes (or power windows, for that matter) and now when I get in the Prius, just lightly touching the brakes feels like slamming on them, and I don't feel the road in the steering wheel as I do in Yevette, and it's not pleasant at all.

All a matter of what you're used to. If you keep driving the Prius, you'll learn to love it. (Unless you decide to go electric, and then you'll be spoiled for ever.)

 

Can you be more exact about the "fade". Possibly, you are charging the battery up into the green, in which case the regeneration mode is greatly reduced, and all you are left with then is the friction braking. Old-fashioned friction brakes alone, are quite a shock when left to them by the Hybrid system. Your hills there might need a bigger battery.

If what you are sensing is truely a fading (by heating of the brake to a temperature which effects its tribologic properties, and/or brake fluid vaporization), like efusco said "What are you doing with that car!".

You might be required to brake to a slower speed in curves due to the handling twitchiness. This can be helped dramatically with the BT Tech plate, and an adjustment of alignment to a slightly positive toe-in, but still within specification. The specification allows for negative toe-in. With this combination, the seat-of-the-pants handling comes right back.

The electric steering seems (i do not know for sure if it does) to have built-in feedback. One does not need to control the steering by the haptic method. Just be sure to point where you want to go, or where you want to thrust the car (which may or may not be the same direction).

 

<div class='quotetop'>QUOTE(dsam1961 @ Jun 8 2007, 12:07 PM) [snapback]458051[/snapback]</div>

Yes, I think it drifts to the right. Very unnerving/

Mary

 

<div class='quotetop'>QUOTE(Masnyd @ Jun 8 2007, 06:45 PM) [snapback]458357[/snapback]</div>

Mary, take it to the dealer and have them check the alignment for free. Ask for the specs "before" and "after" to be printed.

 

<div class='quotetop'>QUOTE(ZA_Andy @ Jun 8 2007, 01:17 PM) [snapback]458122[/snapback]</div>

Our Prius is a dream to drive, and the only issue we have, is that we want to take a short nap, it is putting us to sleep. The transmission is smooth, almost monotonous, and I understand the feeling of a disconnect.

We also have a 76 Mini. The noise, the shifting, the exhilaration of flying by the seat of your pants is far from removed from taking a nap. It's an organic, basic driving experience; press on the gas, it goes, let up and it's like putting on the brakes. I have to be very connected driving it, there isn't a choice. I think the Prius lulls me into thinking there is a choice sometimes, that's the part I have to watch out for.

I love the challenge of both cars. Regarding safety and emissions, they couldn't be further apart, yet both still manage to have good mileage and give a great driving experience. The Mini's charm is basic and easy to see, while the Prius' is more subtle, which just makes it more fun to discover.

 

<div class='quotetop'>QUOTE(JimN @ Jun 8 2007, 08:25 PM) [snapback]458375[/snapback]</div>

Thanks Jim,

You know, I did take it to the dealer to check the drifting. He said that sometimes the road curves in such a way to cause the drifting. But I don't remember any curves or strange changes in the road (I live in Florida). Also it was time for my six month oil change and check up (I've had the car for six months), and he looked at the car and the mileage and would not do anything. He said there wasn't enough mileage. I kind of think maybe the service department at this Toyota is poor. He at least should have checked my tires because the gas stations nowadays don't check the tires, and they wouldn't know how to do it with a Prius anyway.

Mary

 

<div class='quotetop'>QUOTE(Masnyd @ Jun 18 2007, 08:15 PM) [snapback]464387[/snapback]</div>

Mary, tires are tires. They don't know or care what car they are on. Uneven treadwear indicates a problem. Tire stores display posters showing different wear patterns and explaining the causes. If you have uneven treadwear go back to the dealer and complain. Pump up the tires to at least 42/40 for longer treadlife.

 

Hi Dsam...,

Ok, I think I know what is going on. The brakes are regenerative down to 7 mph. Then they revert to friction. The calibration is such, that the friction brakes have less force for the same peddle force.

This can be different than other cars, which have friction brakes that tend to grab as one comes to a stop. In the Prius, it feels like a slight surge as one drops below 7 mph. Which is the reverse of a normal car.

After a while, rather than feather the peddle at low speed, I have learned to subconciously mash the brake peddle at 7 mph. And this was tuff, because I was very used to feathering the brakes at slow speed, to make limo-like stops.