"mm" wrote
The car did not start/stop with a key. It has a button and a sensor that knows you have the fob on you. Yes, the dealer should have explained how to shut the car off. From what I've read, you have to hold the button for a couple of seconds. I can see a panicked driver slapping the button repeatedly instead of holding it for a few seconds. Just like turning off a cell phone, you have to hold the button.
Most throttles are just a cable to the throttle body / airbox. It wouldn't be reasonable to expect a solenoid to move the cable; the added complexity might cause more problems. However, all cars are fuel injected nowadays and they can cut the fuel based on brakes. However, going to all the way lean to no fuel might have ramifications with the cat or valves overheating. OK for a detected panic situation, but I don't think it would be desirable every time the brakes are used.
A mechanical interlock can malfunction resulting in a runaway throttle and be far less safe than nothing at all.
snipped-for-privacy@milmac.com (Doug Miller) wrote in news:hmkfuu$uc8$ snipped-for-privacy@news.eternal-september.org:
under normal conditions,the operator would/should not be applying both throttle and brake at the same time.
However,I question any need or benefit for throttle-by-wire(TBW) in an auto. the old mechanical throttle cable and throttle position sensor at the butterfly works fine,and has less chance for malfunction,particularly on newer vehicles.In fact,TBW is added complexity and cost,and more prone to failure. It violates the KISS principle,too.
As has been demonstrated by the Toyota SW problem,TBW can suffer programming errors,SW glitches,or component malfunctions resulting in loss of control of the vehicle.And there's no backup or redundant system as there are in aircraft.A critical failure and your engine runs away.
after checking Wiki,I found these "benefits" for TBW; "The significance of ETC is that it much easier to integrate features to the vehicle such as cruise control, traction control, stability control, and precrash systems and others that require torque management, since the throttle can be moved irrespective of the position of the driver's accelerator pedal."
IMO,if you need a computer to control your traction or vehicle stability,you should not be driving. If your vehicle needs "stability control",it's an inherently unsafe vehicle,and should not be on public roads.
No, I don't know for sure, and I'm assuming you don't either. So I guess it's open for discussion.
Not in all instances.
While I *might* not want to be able to put a tranny in park while it's moving, I would most certainly want to be able to put it in neutral for the very reason this "snow on the roof" thread has continued for so long.
If my throttle got stuck, whether by a floor mat, an electronic fault, a driver having a heart attack or a car jacker with a death wish, I'd be really pissed if I couldn't pop it into neutral in an attempt to keep myself alive.
Just so ya know, I'm neither in that group nor not in that group. I place no blame because I don't know what happened because I wasn't there when it happened to any of them. All I know is what I think I would do if I found myself in that situation. Brake first, neutral next, shut it off I had to.
The only experience I *can* speak from is with my 1980 Mustang. A faulty control module would occasionally shut the car down. The first time it happened, I was traveling at 70 mph in the left lane of a highway and all the gauges dropped to zero. I said to myself "That's weird!" and calmly put the car into neutral, turned the key to restart it, put it back into drive and continued on down the highway. Granted, there was no need to panic since I wasn't accelerating, but my point is that it wasn't that tough to quickly figure out what to try. I'm pretty sure that some drivers would have freaked out and tried to coast to the side of highway, possibly causing an accident as they slowed down. I'd like to think that if my accelerator got stuck, I'd handle it a similarly calm fashion.
As long as the inputs used are not outside normal limits, and the results (output) are what the inputs are calling for, why WOULD it set a code? If the input he shorted resulted in an input voltage that WAS supposed to result in full throttle accelleration, it would not detect an error. IF however, some stray input (RF or whatever) got into the mix and caused the engine to rev higher than the inputs would indicate (which is what so many who know nothing about how digital full authority engine controls (aka FADEC) works are postulating) the computer WOULD trip a code in all likelihood.
Anything that stops the clock would, by necessity, stop the engine because the clock is required to fire the injectors and time the spark. Absolutely IMPOSSIBLE for the engine to run if the oscillator (clock) of the ECU was to fail. Pretty much the same with a bad ground - as the injectors are ALL powered externally and grounded through the ECU. Also, all the sensors go to higher voltage as the input increases. A ground (Other than the wired signal ground for each 3 wire resistance type sensor) is not required on the majority of sensors, and if that ground went bad the reference voltage would go out of spec, throwing a code or the sensor would be detected as an open circuit (also an out of range value), throwing a different code. About the only thing external that could be causing an accelleration problem would be digital noise entering the system as RFI that just happened to be exactly the right frequency and amplitude , at exactly the right place, to fool the computer into thinking it was a legitimate signal.
Extremely unlikely - not at all like the analogue type fuel injection computers used on the oldD-Jetronic system like the VW412. (and EFI SuperBeetle)
Which is EXACTLY what was just said.
But remember ONLY one to three pumps.
Two is a pretty good guess, and a VERY good reason NOT to pump the brakes.
On many cars with read disk brakes the "parking" brake is a VERY small drum brake inside the rear rotor and will have virtually NO effect on slowing the car at speed, in gear or out.
Because very many drivers will find the effect on driveability something less than desireable?? And just how much authority do you give the brakes over the throttle, and under what conditions, at what road speed, and at what throttle position??
And there is a list just as long that does not. Like most Volvos, Corvette and any rear wheel disk GM and a few of the newer models of just about every one of the brands you noted.
It is when they go for several miles (or even a mile) and then hit something. Even IF there is a malfunction, only driver error accounts for that.
The reported pedal friction problem would account for the increase.
And what about GM's recall for defective power steering???? Not the first one either. If not recalled, they should have been back in 1979-1989?? when steering racks on GMs were getting stiff and causing very severe "pull" to either left or right when the racks wore out at anywhere from about 10,000 miles on up. Different system, and different problem today - but like many susect with Toyota, electronic in nature.
Wheres the bigg hullabaloo now?????
Oh, we KNOW that, because in neutral a car will NOT accellerate unless going down a very steep hill or falling off a cliff.
And the cure for _not_ dieing has been published and should have been known by every one of the victims (provided there was _time_ to react properly). You "totally innocent" stance is groundless. Every driver should know enough about the vehicle operation to take the proper action without having to be told.
Harry K
How about like " I tried it on a Lexus ES300 and you can put it in neutral any time you like, and when in neutral the car slows down, and when floored in neutral the tachometer jumps between 3000 and 4500 rpm"
Truth is stranger than fiction
It doesn't matter that the dealership was at fault there. The primary cause of the deaths was driver stupidity. Had he responded properly, as I hope anyone possting in this forum would, noone would have died.
Harry K
:
!!??? He should have known there was a prolem with unintended acceleration? And just how do you think he could have done that unless the dealer told him? Fixed it!!!? The DEALER can't even find the problem much less fix it.
Harry K
Driver-
Very simple - disconnect power to injectors - that will stop the accelleration. But you need a "computer" of some sort to tell that relay when to actuate, according to throttle, speed, and brake inputs.
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