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Transportation Bug Technology

Toyota Pedal Issue Highlights Move To Electronics 913

cyclocommuter writes with an excerpt from a brief WSJ story on increasing electronic control of car components: "The gas pedal system used Toyota Motor Co.'s recall crisis was born from a movement in the auto industry to rely more on electronics to carry out a vehicle's most critical functions. The intricacy of such systems, which replace hoses and hydraulic fluid with computer chips and electrical sensors, has been a focus as Toyota struggled to find the cause for sudden acceleration of vehicles that led the company to halt sales of eight models this week."
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Toyota Pedal Issue Highlights Move To Electronics

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  • Safety Critical (Score:5, Insightful)

    by Renraku ( 518261 ) on Sunday January 31, 2010 @04:22PM (#30973194) Homepage

    At least in one case, the brakes failed, the accelerator stuck, and the person didn't know how to turn the car off because it was a rental and used a push-button ignition. Also, they couldn't put it into neutral because it had a push-button shifter as well. People really should learn about the car before they drive it, but this is a monumental fuck-up on the part of Toyota. I think that we can do the push-button stuff CORRECTLY, but this isn't the way to do it.

  • by statusbar ( 314703 ) <> on Sunday January 31, 2010 @04:24PM (#30973210) Homepage Journal

    I design computer hardware and software and I always tell people:


    But No On Believes Me...


  • Re:Safety Critical (Score:5, Insightful)

    by maxwell demon ( 590494 ) on Sunday January 31, 2010 @04:26PM (#30973222) Journal

    Well, maybe all-electronic cars should be required to have a highly visible button labelled "Emergency Off" - I think I don't have to explain what this should (and shouldn't!) do.

  • Re:Safety Critical (Score:5, Insightful)

    by Third Position ( 1725934 ) on Sunday January 31, 2010 @04:30PM (#30973252)

    Well, I'm not sure this incident accurately represents the situation. On balance, the electronic components are safer than the mechanical ones. Electronic components can be automatically monitored and compensated for much more easily than mechanical ones. Sure, this incident isn't good, but one of the reasons it stands out is that safety issues caused by deficient electronic component failures are so rare. On balance, accidents caused by component failure in modern cars are rarer than they've ever been.

  • What? (Score:3, Insightful)

    by RockMFR ( 1022315 ) on Sunday January 31, 2010 @04:32PM (#30973276)
    Title: "Electronics parts = Toyota woes"
    Article: "condensation from heaters caused increased friction in the gas pedal, making it stick in some cases, making the problem a mechanical one and not an issue of electronics."

    So electronics had nothing to do with it at all. And their suggestion that the complexity of electronics made this issue harder to diagnose isn't backed up at all.
  • Re:Safety Critical (Score:5, Insightful)

    by Anonymous Coward on Sunday January 31, 2010 @04:32PM (#30973278)

    the person didn't know how to turn the car off because it was a rental and used a push-button ignition

    The problem with any tech is that it's nearly impossible to make it perfect. In some situations like airbags, you can make the system very simple and independent, so it's not prone to failure. But when there are scenarios that result in death, you need to be able to *shut it down* very quickly. In a car, that means literally turning the engine off.

    If you can't do that in the car in question, that's insane. If it's not obvious to do so, it only highlights the life-or-death importance of good interface design, which on most cars seems to be outrageously awful. You should not reasonably have to open a manual to change the fucking clock.

  • Re:Safety Critical (Score:5, Insightful)

    by Concerned Onlooker ( 473481 ) on Sunday January 31, 2010 @04:32PM (#30973288) Homepage Journal

    I'm sure push button transmissions could be done correctly. The problem isn't with the tech, the problem is with standardization. The way things are now is that you can get into just about any car and the shifting will be very, very similar. When you are under pressure you will react the way you've done things the previous thousand times, so having transmission shifters standardized is a kind of safety feature. It would be a big shift (heh) to get everybody to be used to a new way of doing this very basic thing. Would it be worth it?

  • by jo7hs2 ( 884069 ) on Sunday January 31, 2010 @04:32PM (#30973290) Homepage
    It doesn't matter to me if the issue is electronic or mechanical, I want a mechanical peddle pair and a mechanical key switch. I want to be able to kill the machine if I have to, and not rely on the electronics to behave appropriately when malfunctioning. How many press down to turn off power systems have you encountered that failed to turn off after a crash? I've certainly encountered my share of them.
  • by nurb432 ( 527695 ) on Sunday January 31, 2010 @04:38PM (#30973360) Homepage Journal

    There is still no excuse for Toyota not coding the ECU to cut throttle when it senses that the driver has BOTH the throttle and the brakes on simultaneously. All drive by wire VW/Audis are setup this way.

    So you have never 'power braked' as a kid to impress the girls i take it.

  • by arb phd slp ( 1144717 ) on Sunday January 31, 2010 @04:39PM (#30973366) Homepage Journal

    Just because that's what Toyota is focusing on, doesn't mean that's what's actually wrong. They were all about floor mats previously.

  • by SydShamino ( 547793 ) on Sunday January 31, 2010 @04:39PM (#30973370)

    There is still no excuse for Toyota not coding the ECU to cut throttle when it senses that the driver has BOTH the throttle and the brakes on simultaneously. All drive by wire VW/Audis are setup this way.

    Plus this would solve the problem of the drivers that like to ride with their left foot on the brake pedal - accelerating with their brakes on, cruising with their brakes on, braking with their brakes on (but who can tell?).

    Just need to solve hills where the driver may need throttle and brake simultaneously to start moving, and it should work.

  • by CAIMLAS ( 41445 ) on Sunday January 31, 2010 @04:40PM (#30973378) Homepage

    Most throttles are a simple cable system (or, at least, they used to be). Such a system doesn't break often and, when it does break, seems to be a gradual thing. I don't personally see much of a need to change things from such a simple mechanism: it works, and rarely breaks. Added complexity introduces many additional failure points. The failure being solely mechanical still likely points to either a drastic re-engineering to account for the electronics, or an electronics-induced mechanical failure. Cable throttles are not exactly "new" science.

    A throttle really needs to be designed with safety in mind: IE, under-working not over-working. In other words, the car doesn't "go", never mind not accelerating.

    The summary is referring to breaking systems when mentioning hoses and hydraulics. It's already a complex system, but should not be in any way associated with the throttle: breaks should still work when the throttle is broken.

    Really, there's little excuse except poor engineering on the part of the Toyota failures. I don't think it speaks one way or the other, for or against, EVs/electronics in vehicles. There are other, bigger issues surrounding EVs/electronics which aren't even really related. The fact that the Toyotas were 'advanced' vehicles is simply coincidence.

  • Re:Safety Critical (Score:5, Insightful)

    by Shadow of Eternity ( 795165 ) on Sunday January 31, 2010 @04:45PM (#30973440)

    Or maybe we should recognize that multi-ton incendiary missiles capable of travelling at a hundred miles per hour on a level surface should be required to have at least 3 manual systems: Shifting, braking, and emergency shutoff.

  • Re:Safety Critical (Score:5, Insightful)

    by rubycodez ( 864176 ) on Sunday January 31, 2010 @04:46PM (#30973452)

    citation needed. I'd say the opposite, huge number of replaced PCM modules and sensors show electronics are short lived, needlessly complex solutions offered in lieu of time tested mechanical and hydraulic ones. For example, guess what can happen if O2 sensor in exhaust system is faulty, car can drop rpm to idle then rev high in ten second pulses, very dangerous on highway. Happened to me, found myself in 4000 lbs. bucking steel bronco. Computer should not have so much control over throttle, just a small amount of mixture and timing adjustment, not complete potentially deadly control.

  • by FonzCam ( 841867 ) on Sunday January 31, 2010 @04:52PM (#30973536)

    The issue isn't the sticky pedal it's what you can do about stopping a car once it sticks. In a traditional mechanical car you can simply put the car in neutral, pull over and stop. If for some reason you can't get it into neutral then you could still turn off the car by turning the ignition key to off. With a keyless ignition and all electronic gearbox you rely the designers of your drive-by-wire system to have foreseen this type of situation and have included an appropriate failsafe in their system.

    In the case of the runaway Toyota pressing the ignition to turn the car off does nothing (to stop you accidentally turning the car off) and the gear selector wouldn't select neutral (presumably because the accelerator was on full) the correct thing to do is hold down the start button for 3 seconds and that shuts down the engine.

    With mechanical systems you can simply disconnect them and they stop working, with electronic systems you need to know a shutdown procedure and these procedurers are currently specific to each model of car.

  • by jernejk ( 984031 ) on Sunday January 31, 2010 @04:56PM (#30973584)
    Yeah, that's why I'm always a bit nervous when flying with airbus.
  • Re:Safety Critical (Score:4, Insightful)

    by statusbar ( 314703 ) <> on Sunday January 31, 2010 @04:58PM (#30973608) Homepage Journal

    You said:

    So? Why couldn't they put it in neutral with a push-button shifter?

    I think he was saying that the push buttons stopped working because the computer system crashed.

    If that was the case, the only thing the driver could have done different would be to pull the emergency brake.

    There are lots of formal safety and reliability requirements and testing required for fly-by-wire systems in airplanes and helicopters.
    What formal safety and reliability requirements and testing are required for drive-by-wire systems in cars?


  • by Shadow of Eternity ( 795165 ) on Sunday January 31, 2010 @04:58PM (#30973612)

    According to the sibling posts it's because his car didn't allow him to shift into neutral while at speed, which means if the brake doesn't override the suddenly stuck gas pedal and the push-button power switch doesn't want to turn off (just like my computer when it hangs...) he's fucked.

  • by vux984 ( 928602 ) on Sunday January 31, 2010 @05:00PM (#30973640)

    Steps for starting a manual transmission car pointed up a steep grade:

    These are not a manual transmission cars.

  • Re:Safety Critical (Score:5, Insightful)

    by ctmurray ( 1475885 ) on Sunday January 31, 2010 @05:11PM (#30973756) Journal
    On Toyota's with this button you have to hold it down for 3 seconds before it turns off the car. In fact the long time hold has been criticized in relation to these accidents. Since you only have to touch to turn on, when you want to turn off in an emergency you also just poke at the button and nothing happens. In the panic of the moment you don't even consider trying again and holding down for a longer time.
  • by xZgf6xHx2uhoAj9D ( 1160707 ) on Sunday January 31, 2010 @05:28PM (#30973952)

    How do you distinguish between the gas pedal being down due to being stuck versus the gas pedal being down due to someone stepping on it? In either case the sensor is going to report that the gas pedal is down. All the software intelligence in the world is going to have a hard time distinguishing between the identical inputs of PEDAL_DOWN and PEDAL_DOWN.

    You could have more intelligent sensors, perhaps, but then that's no longer a software problem.

  • Re:Safety Critical (Score:3, Insightful)

    by chiui ( 1120973 ) on Sunday January 31, 2010 @05:37PM (#30974064)

    That said, if the emergency brake in your car doesn't slow your car down, your brake system is probably calibrated wrong, and you're going to burn up your front disk brakes much faster than normal because they're doing all the work.

    Virtually NO car except one with a ridiculously under-powered engine and very good rear brakes/tires will stop by rear brakes alone. That's how people have fun at drifting.

  • Re:Safety Critical (Score:5, Insightful)

    by Amouth ( 879122 ) on Sunday January 31, 2010 @05:42PM (#30974118)
    I'd have to say your references to "stuck" or "fraying" cables is heavily due to cost cutting - I've never seen one get stuck on older cars. - I've seen them fray and fail but in each case the linkage was designed so it drops the motor to idle. yes i don't have anything to reference on this other than the years of working with them - the traditional accelerator cable is a bicycle cable - something that can fail yes - something that should be checked yes - something that fails in design to justify a recall?? no - unless they are built wrong.
  • by confused one ( 671304 ) on Sunday January 31, 2010 @05:52PM (#30974238)
    you're off base here. Toyota shut themselves down until they had a fix in place and known good parts. Yes, the NHTSA did step in, as they should, but they did not shut down Toyota. In fact, they agreed that Toyota's plans were "acceptable" and left Toyota alone to implement them.
  • Re:Moving too fast (Score:3, Insightful)

    by jimicus ( 737525 ) on Sunday January 31, 2010 @06:08PM (#30974400)

    IMV, if it's possible to kill the engine on a car that has become a demon possessed mechanical monster, driving it to the dealership is f*cking stupid.

  • by snikulin ( 889460 ) on Sunday January 31, 2010 @06:10PM (#30974420)

    'kill -9 engine' is not enough.
    you forgot about kinetic energy (0.5 * m*v^2).
    One might try 'kill -9 -1' but I wonder what will happen with the Universe.
    Man pages are somewhat ambiguous about its effect.

  • by u38cg ( 607297 ) <> on Sunday January 31, 2010 @06:16PM (#30974480) Homepage
    As opposed to the dozens that get killed because drivers with automatic transmissions seem to think they are sitting in a mobile couch and do things like crosswords or homework or embroidery instead of looking at the road?
  • by Anonymous Coward on Sunday January 31, 2010 @06:18PM (#30974498)

    Before you go bashing the intelligence of the driver you should be aware of some issues.

    First, the car was a rental so the driver wasn't familiar with some non-standard features of the car.

    Second, the car did not have the standard key ignition switch. It has a push button on the dash that turns the engine on or off. But more importantly, when in motion the operation of the button changes. When stopped, you simply press the button and the engine turns off. But when in motion, you must hold the button down continuously for three seconds in order to turn off the engine. Presumably this is to prevent turning off the engine accidentally while driving. This three-second delay doesn't normally occur so only someone who has read the 200 page manual would know that. I imagine that in a panic situation you would press the button two or three times and then give up.

    Third, the automatic transmission has a sport shifter feature. You can move the shifter in a position through a gate so that when you press forward the transmission up-shifts and when you press backward it downshifts. You cannot directly push the shifter into neutral. You have to move the shifter sideways and then up several notches to get to neutral. In an unfamiliar car and a panic situation you would try to push the shifter into neutral like most cars. Instead pushing it forward would just up-shift to a higher gear. In a panic situation, going 120 mph, it might be difficult to figure out how this non-standard transmission works -- that you have to move the shifter sideways through a gate to get to neutral.

  • Re:Safety Critical (Score:3, Insightful)

    by mishehu ( 712452 ) on Sunday January 31, 2010 @06:21PM (#30974516)
    The problem with your from-a-complete-stop example of the parking brake in action is that you still have to overcome static friction even before the car moves. In the case where you are already doing 30 mph and the car starts to accelerate, you've long overcome the static friction holding the car in place, and all that is left to work on the call is dynamic friction. Whether or not the main breaks or the parking brake are able to overcome a still-accelerating vehicle's engine is a different issue. This is one reason I really prefer stick versus automatic - if this were to happen to me, I'd hit the clutch, throw it in neutral and then be able to stop the car, and turn it off once I stop. Sure it might cause some damage to the engine from revving so high, but better that than me & other people dead...
  • Re:Safety Critical (Score:5, Insightful)

    by jbengt ( 874751 ) on Sunday January 31, 2010 @06:21PM (#30974520)
    My gas pedal has stuck as I was coming up to a red light, and it was very hard to stop. I attributed it to the snow on the ground, until it happened again at the next light and I noticed the engine was still revving. I almost crashed until I realized what was happening and put the car into neutral. (unfortunately, I overshot and put the car into park momentarily, which resulted in a slow leak of my transmission fluid that cost about $600 to fix).
    Anyway, in my experience, braking is problematic at best in competition with the accelerator. The brake might be enough to hold the car in place while revving the engine at a stop, but I doubt you could make a reasonable controlled stop at full throttle while at speed. (Your results may vary depending on your transmission, brakes, and engine)
  • Re:Safety Critical (Score:3, Insightful)

    by Anonymous Coward on Sunday January 31, 2010 @06:39PM (#30974680)

    Good information here. [] I would suspect however, if the driver didn't immediately apply full brakes, and instead let them get hot before trying to actually stop the car (because of traffic concerns maybe), they might burn up before the car gets stopped.

  • Re:Safety Critical (Score:3, Insightful)

    by Grishnakh ( 216268 ) on Sunday January 31, 2010 @06:51PM (#30974784)

    Wrong. It IS an issue of electronics. The problem isn't the pedal, it's the "start" button, and the fact that these stupid cars don't have a way to turn them off. Back in the "old" days 10+ years ago, cars had things called "keys". To start the car, you turned the key. To turn off the engine in an emergency, you turned the key the other way. Very simple. Now, they've eliminated the key in favor of some keyless RF crap, and put in a start button. This started with the Honda S2000 which had a bright red "start" button like race cars, but there they had the good sense to retain the key for security and on/off, and only use the button for starting. Now, they're using the start button for everything, and there's no "off" button at all. There's a way to turn it off, of course, but it's completely non-obvious, and completely varies by manufacturer. With rental cars, this is a disaster; who's going to read the entire manual before driving away in a rental car? For instance, in some cars, you hold down the "start" button for 3 seconds to turn off the engine. WTF?? This is just like stupid Windows, where you click on "start" to turn off the computer. Other cars have totally different schemes.

    There should be a law that all cars have a bright red "OFF" button, and all existing start-by-button cars must be retrofitted with them at the automakers' expense. This is a colossal screw-up of the highest magnitude.

  • Re:Safety Critical (Score:4, Insightful)

    by ThrowAwaySociety ( 1351793 ) on Sunday January 31, 2010 @06:58PM (#30974840)

    unless they are built wrong.

    Which is the whole point. There is a right way and a wrong way to build a mechanical throttle assembly and cable. There are also right and wrong ways to build electronic throttles. Either system can be perfectly safe if designed and manufactured with proper tolerances.

  • Re:My idea (Score:3, Insightful)

    by BitZtream ( 692029 ) on Sunday January 31, 2010 @07:30PM (#30975110)

    The solution is to just put the damn thing back on a key.

    There is no actual reason not to use a key, there is no usability increase from using a button and most certainly usability problems from using a button.

    At least make the button a fucking toggle rather than momentary contact.

    Perhaps the idiots should take a clue from people who have doing fly by wire for a lot longer ... aircraft.

  • by BitZtream ( 692029 ) on Sunday January 31, 2010 @07:47PM (#30975278)

    You didn't do much research. Toyota has been having this problem for several years now, its been in the news several times, it has not been fixed, and they keep coming up with new excuses for the problem.

    They don't know, or don't want to admit to it.

    Either way, you're an idiot for trusting them to tell you its safe to drive your car. It doesn't matter how rare it is, its JUST as likely to happen to you as it is every owner. They haven't told the truth or have had no clue what the problem is for several years. Trusting them is about as intelligent as trusting a politician at this point.

  • by OrangeTide ( 124937 ) on Sunday January 31, 2010 @07:49PM (#30975308) Homepage Journal

    so it's OK to take your family into an unfamiliar vehicle? The manual is in the thing, and the fact that it is non-standard is immediately obvious once you try to start it and shift it into drive.

    sorry, but when you are using something unfamiliar that could be dangerous (car, gun, bulldozer, etc) it is customary to receive instruction or to operate it in a controlled environment (parking lot). Maybe I'm just crazy, but when I rented a car and it seemed a little weird(a Honda, I'm used to American cars), that is exactly what I did (drove it around the parking lot at the airport for about 5 minutes).

    Failure to do so can result in the death of you and your family. Sorry, but that's the harsh realities of people who disregard safety. A car is not a toy. And a CHP officer who has likely seen the results of hundreds of fatal accidents should be far more paranoid than any of us when it comes to operating a motor vehicle.

    I blame him because the driver should assume the responsibility for operating a vehicle. And for Toyota for making their car so automated and high tech that it is difficult to operate safely.

  • by couchslug ( 175151 ) on Sunday January 31, 2010 @08:00PM (#30975414)

    The German solution we should copy is a real driving test. In the US, one has to be mentally defective not to be issued a license, driver/rider training sucks, and the result is deadly.

    I could care less about manual boxes. I have both, but autos suit the way I use my larger trucks.

  • by Reziac ( 43301 ) * on Sunday January 31, 2010 @08:42PM (#30975806) Homepage Journal

    Regardless of which is given priority... I'll bet those cars are real fun to drive on glare ice, where you may need to be constantly nursing both the brake AND the throttle, to maintain traction and control direction.

  • by illumin8 ( 148082 ) on Sunday January 31, 2010 @09:47PM (#30976386) Journal

    What is with all these crazy people suggesting that you should shift into neutral? With a floored accelerator, that's a great way to completely destroy the engine. How about you do what you always do when you want to slow down? Push the fucking brake!

    I'd rather shift into neutral and blow the engine than blow myself all over another vehicle or a guard rail at 100 mph... Brakes don't work as well when you're at wide open throttle. Don't be an idiot. A blown engine is easy to replace; in fact, I bet Toyota would give you a free one if you experienced this problem. They'd rather pay for an engine than pay death benefits to your family.

    Bottom line, don't try to be a hero. Let the engine blow if it's gonna, put it in neutral, brake to a stop, and turn off the ignition.

  • Re:Safety Critical (Score:2, Insightful)

    by baegucb ( 18706 ) on Sunday January 31, 2010 @10:59PM (#30976786)

    After a dealer did service on my non-Toyota car a couple years ago, the throttle stuck open about 20 minutes later while on the highway. The brakes were good enough to get it to a stop and I then shut off the engine. Scary for a few minutes but it worked. They had examined the throttle cables for some reason and put the cover back on incorrectly, causing it to later jam.

    The problem with Toyotas I expect will come down to an electronics problem, not a mechanical one like I had. Seems to me that they are trying their best to put the blame on anything else expect their software.

  • Re:Safety Critical (Score:3, Insightful)

    by statusbar ( 314703 ) <> on Monday February 01, 2010 @01:26AM (#30977662) Homepage Journal

    Well that blows a hole in that idea, then!
    What could this guy have done in this situation? He can't un-press the gas, he can't press the brake because the CPU gives the gas precedence if you press both, the emergency brake would cause him to go out of control, and he can't shift gears because that is under software control too!!

    quite the conundrum!


  • by BZ ( 40346 ) on Monday February 01, 2010 @02:11AM (#30977876)

    > Then you have to move to a city where this is possible.

    There are not enough such cities in the US to hold its current population, or even any significant fraction thereof.

    > Again, you don't have a right to live wherever you want.

    You also don't have a right to not slowly starve to death in the street, really. Nor do you have a right to live anywhere at all.

    None of which is useful in terms of dealing with society as a whole. If 10% (rough guess; I would be very surprised if the threshold is above this) of the population is homeless, you end up with civil unrest. If 20% of the population can't find a place to live where they can hold down a reasonable job, almost certainly the same thing will happen.

    > Choose a job closer to your home (or on a better location WRT the bus route)

    You seem to have a mistaken impression about how many such jobs there are.

    > There's no right to a job.

    Indeed, or to breathing if you want to look at it that way. Again, that's not useful for setting up a society.

    > But McDonald's is always hiring

    This is in fact false.

    > and it shouldn't be hard to find a place where you can walk to work at McD's and live
    > within walking distance at some cockroach-infested apartment

    For any one person, perhaps. For a significant fraction of the population, this would in fact be difficult: McD's simply doesn't need this many employees.

    > You don't have a right to the job you prefer.

    See above.

    > We "invested" a bunch of money in a light-rail system here in Phoenix/Tempe, and it's
    > been a disaster.

    Hey, I'm not talking about graft, people building bridges to nowhere, people screwing up, etc. I'm saying that even in the best case, with the best of intentions, people are _still_ bad at major non-incremental infrastructure investment. Which is why ideal infrastructure investment would be incremental: build a small piece that's immediately useful and then work out from there. That turns out to be pretty hard.

    > The problem is our cities are already designed for cars

    They were designed for pedestrians and carriages in 1890. Designs can be changed if the alternative is good enough or enough money is trying to push the changes through (or ideally both). In the case of alternatives to car transportation, we just aren't there.

    SkyTran would be nice if it could happen, perhaps, but I predict we'll get cars that can drive themselves (given a combination of sensors and GPS) way before we could convince people that SkyTran is a good idea, much less get elected officials to act on it. Then we'll have the fun of scare stories about them running over pedestrians, and they will in fact run over pedestrians. Could get interested.

    > Instead, we have politicians, who waste money on crap

    Fundamentally, people want stuff for themselves out of a government. Each of them only wants a little bit, really, but we have 300e6 of them or so, and a nontrivial portion of them are trying to get more stuff all the time. Such things never get rolled back, typically (politicians like getting reelected) so if there is any success in getting stuff out it just all agglomerates.

    I have a hard time seeing this social dynamic changing as long as you have universal suffrage. The only hope is that productivity growth remains high enough that the constant drain is not too bad. I'm not sure that'll happen.

    Of course getting rid of universal suffrage would bring its own issues.

    In the end, there aren't any magic bullets or simple solutions here, much as you seem to want there to be some...

  • Re:Safety Critical (Score:3, Insightful)

    by dgatwood ( 11270 ) on Monday February 01, 2010 @02:38AM (#30977990) Homepage Journal

    That's a wildly incorrect oversimplification.

    First, accelerating from 0 to 100 takes much longer in large part because of gearing. You have different amounts of power in different speed bands. That 0-60 time measurement is the *average* of its power, but the brakes must overcome the motor in its *strongest* band.

    Second, you're forgetting that it has to overcome both the engine *and* momentum.

    Third, when brakes are overworked, they get hot and lose their grip.

    I stand by my statement that I would not expect cars to be able to reliably stop with the engine at full throttle. Some might, but I wouldn't bet my life on it. For sure, according to Consumer Reports [], at least one Toyota model cannot reliably do so.

  • Re:Safety Critical (Score:3, Insightful)

    by Hognoxious ( 631665 ) on Monday February 01, 2010 @08:06AM (#30979450) Homepage Journal

    The brakes in cars aren't designed to overcome the engine.

    Press the brake without dropping the clutch and see what happens.

    As someone who's between auto and manual a few times, I speak from experience.

  • by CausticPuppy ( 82139 ) on Monday February 01, 2010 @10:14AM (#30980566) Homepage

    Brake fade is what happens when the brakes get overheated, they become less effective.

    However, what happens when the engine is at wide open throttle is the same thing that happens when the engine is off: you lose vacuum assist. You'll have enough for maybe 2 pumps of the pedal and that's it. Once your vacuum assist is gone, you're relying 100% on the pressure of your foot on the brake via the hydraulic system to stop the car. If you've ever tried to use the brake pedal when coasting with the engine off, you know how hard that is.

    So if you are ever in a "unintended acceleration" situation, push the brake down as hard as you can and do NOT let it back up. You will probably destroy your brakes in the process but that's better than the alternative.

    The whole move to electronics is somewhat disconcerting. Computer software will always have bugs, and modern cars have computer software that controls the throttle, and the transmission shifter. Always make sure you know how to shift into neutral in a panic. On my car, it's easy: just push down the clutch pedal.

  • by Anonymous Coward on Monday February 01, 2010 @01:09PM (#30983148)

    Two big caveats with that test --- first is that the brakes were in good condition to start with, second is that the driver immediately applied full panic braking effort. What about a car with 30K miles on the brakes. What about the situation where you're driving down a busy freeway at 80mph, is your first reaction going to be to apply panic braking? No, you'll be afraid of being rear-ended...

Perfection is acheived only on the point of collapse. - C. N. Parkinson