Article to explain why Toyota pedal fix may not be so good

Patrice Bousquet · **Posted:** Fri Feb 05, 2010 9:33 am

DickRasmussen wrote:

Probably not. At least half of the Prius drivers I see treat the speed limit as something they can ignore by a wide margin . . . either that or they have stuck throttles.

I guess I never encounter the half you are talking about??? every Prius I see is @%&& slow!!!!!!

BriceJohnson · **Joined:** Thu Apr 13, 2006 7:33 am **Posts:** 2230

I was just thinking this last night. For the next month or so, Toyota drivers have carte blanche to speed at will. If they see a cop come after them, just floor it, shift into neutral, turn the car off, and coast to the shoulder. When the cop gets to the window, "Officer, thank goodness you were here just in case, I was SO scared. . ."

MikeWhitney · **Joined:** Wed Aug 20, 2003 9:15 pm **Posts:** 4724

Donnie Barnes wrote:

MikeWhitney wrote:

I've seen several references to "fail safes" and the "lack" of them on the Toyotas. Problem is, to the car's computer this fail mode just looks like someone having a good time -- WOT for extended periods of time. Short of putting some kind of pressure sensor on the pedal, I can't conceive of a fail-safe that could intervene.

Except of course a "maximum WOT duration" limit. Oh joy, a car that shuts down if you're into the gas for too long. I wonder how long it will be until cars can't be hurtled down the straight at your local race track....

The greenies in Washington will probably decide this is a good way to reduce Global Warming too and mandate it via the EPA

Porsche and some other manufacturers already have the perfect fail-safe mode for this...they cut ignition when you press the brake very much while lots of throttle is input. Left foot brakers hate it, but it's effective for this very "problem." It can also be aftermarket tuned out on Porsches, anyway.

--Donnie

Agreed that is a good safety "feature" but it's not a fail-safe. Just pointing that out...

Failsafe means controling of the outcome of the failure. Redundant potentioneters in the pedal is a failsafe since the car could still be drieveable. Adding a pressure switch which cuts power when the throttle input doesn't match the applied force would be a failsafe which allows pedal failure to result in the safe (idle) outcome. Throttle cut when braking means that the fail has already occured in the "unsafe" outcome and we're trying to contain it...

Not arguing, just making a philosphical engineering point

Jason Mauldin · **Posted:** Fri Feb 05, 2010 11:20 am

MikeWhitney wrote:

[

Failsafe means controling of the outcome of the failure. Redundant potentioneters in the pedal is a failsafe since the car could still be drieveable.

That's not failsafe. There's still a single-point failure that doesn't mitigate the risk. (A stuck pedal)

Failsafe does allow for the product to just stop working assuming there is no risk with that condition, or in this particular case, less risk than continuing at WOT. An airplane would be a good example where shutting down is not a failsafe option.

Richard Casto · **Posted:** Fri Feb 05, 2010 2:39 pm

I like the idea of the load cell that makes sure there is force applied to the pedal. No force, no throttle. Even then I think you need something beyond that such as detection of application of brakes, transmission shifted into neutral or attempts to turn off engine via power off button then trip into "safe" mode. Safe mode would not shut off engine, but return to idle or near idle throttle position.

To prevent accidental tripping of this via brakes, the brake pressure would have to be something significant. Maybe 75%+ pressure for a second or so. Might be a pain for left foot brakers as earlier noted. Overall, I think a well designed pedal should prevent sticking. It sounds like Toyota just has a design that when worn can stick.

Marty Howard · **Posted:** Fri Feb 05, 2010 3:39 pm

Vincent Keene wrote:

Quote:

Toyota uses two different electronic gas pedal designs in its cars.

There's your problem right there. Why the hell does a gas pedal need to be electronic? The whole DBW thing sounds like something a German engineer would come up with and use. I thought the Japanese were smarter. Guess I was wrong.

Going back to this for a moment. The manufactuing gains made by "By Wire" systems is huge for a global company. No full engineering excercises to switch from one drive side to another. Easier use of the same engines or components in multiple models. Better traction control and economy systems. The list goes on and on.

But they do need to sort out this issue and system redundancies.

Jason Mauldin · **Posted:** Fri Feb 05, 2010 3:43 pm

I really think Mike has a good solution. Pressure sensor on the face of the pedal. No pressure or no cruise set = no power. It's an easy solution for future products, but not so easy to retrofit.

Richard Casto · **Posted:** Fri Feb 05, 2010 4:47 pm

I would love to know if there are statistics on how many people have plain old fashion sticking throttles that cause accidents vs. the current Toyota situation.

My point being there are probably more people killed by worn components (such as tires) and deferred maintenance related items than design defects. Still Toyota needs to fix this.

steve remchak · **Posted:** Wed Feb 17, 2010 8:34 pm

so this evening CBS News is reporting that several Governors of states that have Toyota plants within their borders are claiming the Gubbernment is unfairly persecuting Toyota in an effort to bolster GM.

ulterior motives due to the Feds "ownership" of General Motors. yep, Obama wants to cause all those Toyota employees on American soil to lose their jobs. i have read the manifesto, it's right there on page 43. :roll:

Arthur McDonald · **Joined:** Fri Aug 29, 2003 1:54 am **Posts:** 2052

I finally heard an explanation today of why you might not be able to stop a car with the throttle stuck wide open: If you just stomp on the brakes you'll probably stop just fine, but if you pump the pedal you'll find out there's no more vacuum in the power brake booster....

But wait, there's more: http://abcnews.go.com/Blotter/RunawayTo ... id=9867318

Keith Vail · **Posted:** Thu Feb 18, 2010 10:05 am

For an example of what is happening to the Corolla steering. Here is one on a Lexus.

http://www.youtube.com/watch?v=MLHWgAmx3Iw

Aaron Buckley · **Posted:** Thu Feb 18, 2010 10:29 am

Keith Vail wrote:

For an example of what is happening to the Corolla steering. Here is one on a Lexus.

http://www.youtube.com/watch?v=MLHWgAmx3Iw

Wow. That is downright scary. - AB

RodneyWright · **Posted:** Thu Feb 18, 2010 10:57 am

Keith Vail wrote:

For an example of what is happening to the Corolla steering. Here is one on a Lexus.

http://www.youtube.com/watch?v=MLHWgAmx3Iw

good Lord.... That WAS scary!

jakepressley · **Posted:** Thu Feb 18, 2010 11:34 am

I've been fascinated by the governments reaction to these problems. Has anyone ever considered Toyota's sales last year compared to two companies now owned by the government?

Seems like a smear campaign to me, compounded by hyped up media coverage.

Removing tin foil hat

My rule is to never buy a Toyota past 2003... The year they started building them in KY.

steve remchak · **Posted:** Thu Feb 18, 2010 12:30 pm

jakepressley wrote:

I've been fascinated by the governments reaction to these problems. Has anyone ever considered Toyota's sales last year compared to two companies now owned by the government?

Seems like a smear campaign to me, compounded by hyped up media coverage.

Removing tin foil hat

My rule is to never buy a Toyota past 2003... The year they started building them in KY.

drank the KooL-Aid did we Jake? :lol:

i'll bet it is NASCAR behind the smear tactics. didn't have these problems when Buick was in NASCAR. :twisted:

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Article to explain why Toyota pedal fix may not be so good

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