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Toyota uncontrolled throttle 6

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thruthefence

Aerospace
May 11, 2005
733
Regarding the Toyota troubles currently in the news; any chance of this being a "drive-by-wire" software (or hardware) issue, as opposed to a strictly mechanical, binding throttle linkage,ect problem?
 
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Damn, I still want a Supra though...[bigglasses]

[peace]
Fe
 
Yes, probably a good time to buy a Toyota.

Now things get weirder, the pedal maker says that the pedal issue is not a likely cause of SUA


and I don't suppose this bloke from NJ believes either of the recalls would help




Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Just for piece of mind, I think if I owned one of the cars in question right now, I would be finding a wire that if cut, would cut of all power to either the ignition or the fuel pump, and I would install a big red safety cut out switch off an industrial machine so that when it is activated it cuts fuel supply and/or ignition at the source.

Regards
Pat
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I'm a bit surprised by the number of people who don't know if they can select neutral while driving their particular car.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
I'm a bit surprised by the number of people who don't know if they can select neutral while driving their particular car.

I have been interested in that question from the first suggestion, but have not seen it convincingly confirmed or denied, which is odd, seeing as how crucially important it is with a runaway engine scenario.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &
for site rules
 
The second linke Greg posted yesterday infers the Avalon can be shifted to neutral since the owner was reportedly doing it while the engine was revving. Don't know about any other models though. That article also says the tech "tried" to move the pedal but could not get the engine to quit revving.

Unless I personally have seen the problem or know someone who I trust that has seen it, I'm really not very convinced that Toyota has anything more than an issue that has been reported in a small number of cars and that they've been trying to diagnose it - as of now, they have found the pedal can stick and have concluded the pedal assembly is the problem. Only time will tell if that is so.

Once this started, the stories begin to circulate out of control. The idea that Toyota is hiding problems is great cover for the media and the lawyers love it too. Now, how many cases of people pressing the wrong pedal will just get blamed on Toyota building a faulty car?

It reminds me of the government here deciding to change the laws to add a bunch of roadside penaltes which remove the court system from the process. They used "street racing" to justify it. Just rattle on about how the law will solve the rash of street racing deaths and let the media run with it. It got competely retarded to the point that every single fatal accident was reported as "possibly street racing" that summer.

Anyone who thinks that the news media exists to report the facts is very dillusional. The news media exists to make the owners money....
 
Looks like they just recalled all of their hybrids now due to a brake that doesn't really brake as hard as it should (something to do with the ABS system).

Dan - Owner
Footwell%20Animation%20Tiny.gif
 
From my very first post, I have been skeptical of the "mechanical only" cause. All this may indeed end up as an execution in mass hysteria...then again!

I have a few basic problems with ALL new cars that do not have a "key", "switch", that when activated kills the engine...RIGHT NOW, not in "three seconds".

Relying on the brakes to save you is a fools dream. In most cases of high speed acceleration, the brakes will simply fail if the power input cannot be interrupted by declutching, selecting neutral, kill switch or the like.

As most of you already know, I still drive race cars and have spent many years doing stupid "driver errors" that, for a non racer, could have been fatal. The ability to save 'ur a** in a clutch situation is only learned by actually doing it or by taking a class in such maneuvers and lots of practice. It must become a "reflex action" it it is to be affective.

Bottom line...Driver education. Common sense driver training classes in avoidance, panic, imminent crash, etc.

Too bad I do not see any of that in the future...Just more "safer cars" mandated by big brother.

Rod
 
Not do defend the media, but Toyota has a history and reputation of denying most field problems and blaming them on 'user error'. Coupled with their reputation for flawless dependability they set themselves up to some extent for this kind of fall. There are many similarities to Ford/Firestone themes where SUV's reputation as the 'safe' vehicle was questioned in a time of economic anxiety. Perhaps the long-term outcome of the current crisis will be similar for Toyota. And just as tire pressure sensors have been introduced, look for an engine kill feature to be marketed or mandated to respond to stakeholder demands created by the situation.
 
I was hoping this would be the death of DBW, but clearly the legislative reflex of adding yet another layer of crap will prevail.

Yeah, I know how simple a kill switch can and should be; wait till the guvvamint gets through with it.



Mike Halloran
Pembroke Pines, FL, USA
 
That's because this is what they think a "kill switch" does.
[cannon][auto]

[peace]
Fe
 
Just an idle thought. How many cases of SUA, or if you prefer, stuck throttles have been reported on manual trans cars that share components or software with the autos?

Incidentally this report is going for the jugular, but notice how the verbatims in the appendix (what the customer actually said) don't agree with the report that was entered into Toyota's warranty system. No wonder T wasn't taking them seriously. Unless that's what the service guys were told to do...




Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Interesting looking report Greg. I'll have to read that further later.

Funny though, I read the summary and it seems to be hinting that there is an electronic problem. Then, it says that brake to idle, which would be an electronic fix, may be the solution.
 
I've read in the paper, that in the event of an accident, the cops can forensically dump the memory of many car's ECU, get information like vehicle speed, braking, deceleration, ect. Anyone know if the suspect Toyotas are able to be inspected in such a manner?
 
Thanks Greg. It took me a long time to read it. One statement just jumps out..."...the blame the driver tack was immediate..." something like that.

After reading the owner complaints, it is not hard to see that there is something more than a simple "shim" will fix.

Also, I found it odd that in the several occasions where the driver had the ability to select neutral, the engine simply over revved...apparently NO rev limiter.......???

I tried to simulate the unintended acceleration in the wife's Lincoln (with her protesting, I might add). The engine rev limiter dropped the rpm to 3000/3500 immediately selecting neutral. Also found that the ECM will not allow reverse at speed...good to know. Oh well, I'm NOT in Toyota's demographic anyway!

Rod
 
Reading some of the complaints is does sound like there is another issue.

I will say that I've had several issues with my C5 Vette accelerating while I was braking. Actually, it's more that it won't slow down even when I'm braking. When I depress the cluth during these events the engine revs up. However, I just move my right foot a little further to the left and the problem goes away...
 
Good idea for you to stay clear of a Mini Cooper, Lionel.

Rod
 
""I tried to simulate the unintended acceleration in the wife's Lincoln (with her protesting, I might add). The engine rev limiter dropped the rpm to 3000/3500 immediately selecting neutral. Also found that the ECM will not allow reverse at speed...good to know.""

The modern automatic shift system is actually quite refined. Most if not all auto shifters will go from drive to neutral by merely pushing the lever forward. You don't have to push the release button. Also the shifter will only go to neutral when you do this. It won't go to reverse unless you push the release button. Additionally most automatic shifters are mechanically connected to the trans so the shift to neutral is mechanical enough that it will shift to neutral without electronics.

In addition there's no way you can damage a DBW system by overevving, all are limited at redline in gear and most have a lower limit, 3,000 to 4,000 when in neutral or park.

IOW these cars are designed to be easily and safely shifted to neutral, and that is the easiest safest thing to do with a stuck throttle. Why the media is spending so much time reporting Toyota's downfall and all the problems and not telling people what they need to do, with ANY car with a stuck throttle, is indicative of their ignorance and their "public service" is lacking.

The fact that people are dying in stuck throttle cars is also indicative of the poor level of driver education in this country. If you can breath you can get a license. If people were trained to shift to neutral nobody would have died.This is something that should be added to all drivers ed courses because with the added complexity of DBW technology there is greater chance of things going wrong.

It would be interesting to see an engineer from a specific discipline related to trans control and/or throttle control weigh in on this thread.
 
""Most if not all auto shifters will go from drive to neutral by merely pushing the lever forward. You don't have to push the release button. Also the shifter will only go to neutral when you do this. It won't go to reverse unless you push the release button.""

What this also means is you do not have to carefully "hunt" for neutral and worry if it's going into reverse or park, you merely slam the shifter forward in an emergency. It can only go to neutral if you don't push the release button.
 
Sorry Chris. The wife's LS won't select neutral without pushing the little thingy....Then it quite easily goes all the way to reverse. It did not, however, select reverse, only neutral and the revs dropped immediately to 3000/3500 !

One of the fatalities lately, the Lexus in San Diego, was driven by a CHP veteran and safety instructor...That suggests some level of advanced experience, does it not?

One instance at a local Toyota dealer indicated that neutral could not be selected. ??? Another, the brakes failed to control the speed and the driver was able to "hold the off button" for the requires three seconds. A third driver selected neutral and the engine "revved uncontrollably" to the point of needing replacement from the dealer! Go back and read Greg Locock's post and inclusion, there are many more complaints filed with Toyota.

Many engineers posting here, including Mr.Locock, ARE experienced in the DBW and SBW systems in use today.

I don't think the "media" has gone overboard with this problem. Quite the opposite, in fact.

Rod
 
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