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Comment by csmeder | Hacker News Reader

Didn't Woz say he can repeat the bug at will? Therefor we know it is a software problem?

Woz found a software bug in the cruise control mechanism. However once you hit the break the cruise control immediately disengages and thus the bug is "fixed". They can fix this bug but it is not a live-or-die issue because there is definitely a way to stop the car.

Won't a stuck accelerator pedal also be remedied by simply pressing the brakes or shifting into neutral?

I the case of the runaway Toyota cars in the news currently, the reports from people are that they do NOT stop with the break engaged. In fact, the recent incident under investigation in California involved the car at a speed of 90 mph until the emergency break was applied decreasing it to 50 mph. For the neutral part, I haven't seen a clear answer. I've heard rumors that the Toyotas either couldn't shift into neutral or the person was too panicked to do so.

the person was too panicked to do so.

Not to sound like a jerk, but if you're too panicked to do this, maybe you shouldn't be piloting a several thousand pound piece of steel around...

Also, this supports my belief that every driver should have to know how to drive a vehicle with a manual-shift gearbox. Shifting into neutral would probably happen without much of a second thought for somebody who normally drives a stickshift.

The California case is currently being subjected to intense scrutiny.

Here's the full, 24-minute 911 call audio. Does that sound like genuine panic to you? How would someone who doesn't know how to stop a car have any idea if their "brakes are almost burned"? http://jalopnik.com/5489553/runaway-prius-911-tape-im-over-9...

The driver filed for bankruptcy in 2008, and still has $700,000 in debt. http://jalopnik.com/5491101/did-bankrupt-runaway-prius-drive...

There's significant reason to suspect this guy may have attempted a pretty blatant cash grab.

Regardless, I think the Corolla is the only Toyota sedan that still has rear-drums. I believe all others (maybe barring the bottom-rung Camry) are 4-wheel discs. The brake systems on Lexuses are also significantly beefier (though nowhere near sports car territory). C&D did tests with Mustang GT500s -- which while having beefier brake packages, aren't anything compared to normal supercars and high-end sports cars -- had no problem stopping a 500HP engine from 120mph while maintaining wide-open-throttle. Sure, it took some distance, but it definitely stopped. My point is, if you step on the brake pedal and don't release, ANY car that is properly maintained will stop.

Oh I know, when I said "the reports from people" in my parent comment I really meant that. Even before today's news I thought the CA case was fishy, so your comment is preaching to the converted a bit :-) I strictly meant that the drivers report to have tried to apply the brakes as hard as they can in most (all?) of the cases.

On a side note, I recently had a stuck accelerator less than a week ago. (No it isn't a Toyota) Since I drive a manual transmission, I just quickly clutched and shifted to neutral. The engine redlined a bit before I killed it, which isn't good, but no serious harm to anyone or machine as far as I can tell. I coasted to a stop and then pulled the gas pedal from the floor with my hand. The weird thing is, after your comment just now I was trying to remember whether I tried to apply the brakes and I don't remember. It is cliche, but it "happened so fast," haha.

In some cars there is electronics that will stop the gas when the brakes are applied, but many brans (including toyota) do not employ these electronics.

So, if the gas is stuck and the brakes are both applied they will act in opposition, and with most engines the engine will overpower the brakes. So, applying the breaks will slow it down (especially if you apply normal and emergency breaks together), but it probably will not stop.

I vaguely remember a newscast where someone did apply both brakes and it slowed them down from some extreme speed to somewhere around the 40s or 50s.

Come on people, let's see some cited examples of engines overpowering brakes!

Car and Driver actually did a test (http://www.caranddriver.com/features/09q4/how_to_deal_with_u...), and even a hot (540HP) Roush stage 3 Mustang didn't overpower the brakes at 70MPH.

Thanks for the link. I was unaware of the test. I was basing that on the news reports that said that was what happened when they tried to brake.

I don't believe for a moment that the engine will overpower the brake, for the simple reason that any normal car can stop faster than it can accelerate. That means the brakes are stronger. For sure a Camry or Prius can in no way accelerate faster than they stop.

Yes, there is an issue with overheating the brakes, but that will take a fairly long time, certainly longer than the time it should take you to figure out wtf is going on and shift to neutral or turn the ignition off.

IMHO, the outcome of these incidents being someone dying has driver error written all over it, even if the runaway acceleration actually is real.

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