Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

[Brian Lohnes]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

How many millions of vehicles were recalled due to mechanical throttle cable or linkage failures?

the best question in this whole post. Who knows the answer to that?

I still disagree that the Toyota throttle control in question has more parts, or has more to go wrong, than a typical cable throttle.

Who here has taken apart an APPS system anyways?


The throttle pedal turns a simple potentiometer (the ones I have seen, have a pair of pots). The potentiometers have THREE wires: a ground, a power supply (5 volts), and a signal return into the ECU. That's HALF of the "throttle control" and already, no pulleys, cables to worry about bending (or adjust), etc.

The second half of the control, which wasn't even the issue in the Toyota case, is a servo in the TAC module, with a pair of inputs to control it. It's controlled just like the Idle Air Motors on GM cars, 4 wires (two circuits, one to open and one to close). The ones I have seen, double up on these andphysically can't "overcenter" like Captain Genius thinks.

I still say, it's incorrect to claim that the DBW setup is guaranteed to fail more often than a manual, cable driven throttle control. I think that it's been proven already, as well (but not sure about that). Nobody here can cite how many recalls happened with cable throttles... so... sounds to me like there's not enough info here to jump to conclusions.


And besides, the failure on the toyotas (if this information is indeed fact) is MECHANICAL. They're replacing something that regulates friction in the pedal. Pretty lame, if you ask me, to call this a "drive by wire" problem when what's happened is simply a failure of a pivot or hinge point. Yeah it sucks for the families who are losing their loved ones, and SCREW toyota for cheaping out on parts and releasing something so problematic, BUT - it seems really lame to me to be writing this off as a "DBW is too high tech and fails more" kind of problem when nobody here has facts to back that up.

Carry on!

I can see where Jim is coming fron on blaming DBW because the component that failed does not exist on a normal mechanical system. That part is there because the car is DBW right?

[min301]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

Correct.

[dieselgeek]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

I can see where Jim is coming fron on blaming DBW because the component that failed does not exist on a normal mechanical system. That part is there because the car is DBW right?

From what I can tell, it's a hinge with a little friction built into it. It's about a 50/50 call saying "that part wouldn't exist on a cable throttle" because, there are MORE pivot points on cable throttle assemblies.

I'm not being the "Pro Electronics" guy here, I'm simply being a Realist. The alleged bad part is a pivot at the top of the pedal which can be argued, exists in any other throttle. Some of them use bushings, some use ball bearings, some add friction and some don't.

[IRONHEAD]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

cable pivot points . the pedal and the throdle blade shaft same as the wire

[squirrel]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

The way you're defending DBW, it sounds like you have the patent for it or something. Sheesh.

Count the number of moving parts in each system. Which has more? It's not rocket science.

Mechanical throttle systems were used for over 100 years, and there have been plenty of problems with them. It's only in the past 30 years (roughly) that carmakers have actually been held liable for their bad designs, so only recently have they spent a lot of effort towards making them mostly foolproof.

As overal vehicle quality has improved so much recently, it is now possible to make complicated systems like FBW actually work. But it's still a more complicated system, that needs a lot more effort put into it to make it work reliably than a simple mechanical cable.

Sometimes I wonder about you Scott, you seem to want to defend electronics to the death. It's not that big a deal to me, I know that computerized stuff can be made to do wonderful things. I just question sometimes if it's worth it. I think FBW is one case where it might not be worth it.

As for the damper existing in FBW and mechanical systems: I don't know of any need to intentionally introduce friction in a mechanical system. That's the whole issue here...the damper is a designed in bind, which is not needed with non DBW throttle.

[dieselgeek]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

The way you're defending DBW, it sounds like you have the patent for it or something. Sheesh.

Count the number of moving parts in each system. Which has more? It's not rocket science.

Mechanical throttle systems were used for over 100 years, and there have been plenty of problems with them. It's only in the past 30 years (roughly) that carmakers have actually been held liable for their bad designs, so only recently have they spent a lot of effort towards making them mostly foolproof.

As overal vehicle quality has improved so much recently, it is now possible to make complicated systems like FBW actually work. But it's still a more complicated system, that needs a lot more effort put into it to make it work reliably than a simple mechanical cable.

Sometimes I wonder about you Scott, you seem to want to defend electronics to the death. It's not that big a deal to me, I know that computerized stuff can be made to do wonderful things. I just question sometimes if it's worth it. I think FBW is one case where it might not be worth it.

You're mistaken Jim. I'm not "defending electronics to the death" but, I simply defend what I perceive as someone citing their biased opinion as "factual" and, unfortunately, I see no problem here other than bad engineering of a mechanical part.

You ask about the numebr of moving parts - I see fewer moving parts in the APPS/TAC schematic than I see in a cable throttle, unless you consider solid state electronics "moving parts?"

I've said it many times, I personally prefer a cable throttle. I see no one here citing reasons WHY we have DBW but it MIGHT be that they were shown in testing to be MORE reliable than cable throttles? We've all seen cable throttles break or stick - hence the rules in LSR and Drag acing about multiple throttle return springs, etc.

So, I'll defend that the problem isn't "DBW" because, even if the Toyotas in question still ran cable throttles, there could have easily been the EXACT same problem - inconsistent friction control at the throttle pivot point - with the cable throttle.

Note, I feel that you seem to defend "non-electronic controls" to the death, but I know from talking with you it's because (a) there's a long history of parts that simply "work" and (b) that you like the old stuff. I respect that. Sure, I like electronics, and I'll gladly bash the electronics that CAUSE ACTUAL PROBLEMS but in this case, nobody has com even close to showing that the problem here is worth blaming the "Drive-By-Wire" system.

[Brian Lohnes]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

So far my research has not turned up an NTSB or manufacturer recalls due to sticking mechanical throttle systems. There have been several manufacturer recalls due to fraying/breaking throttle cables (the last seems to be late 1990's dodge trucks) but none mandated by the government and none that I can find which caused the throttle to hage wide open.

I'll keep looking to see if I can find anything. I'm not trying to make the above observation some end-all be all answer, but it was a question that popped into my head and seemingly could be answered...

Brian

[IRONHEAD]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

The way you're defending DBW, it sounds like you have the patent for it or something. Sheesh.

Count the number of moving parts in each system. Which has more? It's not rocket science.

Mechanical throttle systems were used for over 100 years, and there have been plenty of problems with them. It's only in the past 30 years (roughly) that carmakers have actually been held liable for their bad designs, so only recently have they spent a lot of effort towards making them mostly foolproof.

As overal vehicle quality has improved so much recently, it is now possible to make complicated systems like FBW actually work. But it's still a more complicated system, that needs a lot more effort put into it to make it work reliably than a simple mechanical cable.

Sometimes I wonder about you Scott, you seem to want to defend electronics to the death. It's not that big a deal to me, I know that computerized stuff can be made to do wonderful things. I just question sometimes if it's worth it. I think FBW is one case where it might not be worth it.

You're mistaken Jim. I'm not "defending electronics to the death" but, I simply defend what I perceive as someone citing their biased opinion as "factual" and, unfortunately, I see no problem here other than bad engineering of a mechanical part.

You ask about the numebr of moving parts - I see fewer moving parts in the APPS/TAC schematic than I see in a cable throttle, unless you consider solid state electronics "moving parts?"

I've said it many times, I personally prefer a cable throttle. I see no one here citing reasons WHY we have DBW but it MIGHT be that they were shown in testing to be MORE reliable than cable throttles? We've all seen cable throttles break or stick - hence the rules in LSR and Drag acing about multiple throttle return springs, etc.

So, I'll defend that the problem isn't "DBW" because, even if the Toyotas in question still ran cable throttles, there could have easily been the EXACT same problem - inconsistent friction control at the throttle pivot point - with the cable throttle.

Note, I feel that you seem to defend "non-electronic controls" to the death, but I know from talking with you it's because (a) there's a long history of parts that simply "work" and (b) that you like the old stuff. I respect that. Sure, I like electronics, and I'll gladly bash the electronics that CAUSE ACTUAL PROBLEMS but in this case, nobody has com even close to showing that the problem here is worth blaming the "Drive-By-Wire" system.

cable, what fiction control???????
the return spring??
as far as moving parts
pedal both
throttle blade shaft both
cable one..
stepper motor one

tps both if efi
how do you figure the cable has more moving parts.
if anything it has less parts total.. as it isn't require'n a wire harness to the pedal to the ecu and to the throttle
it's a pedal, a cable a bracket and throttle shaft..
what parts did I miss when I installed the new cable in my s10

[squirrel]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

but in this case, nobody has com even close to showing that the problem here is worth blaming the "Drive-By-Wire" system.

The problem is caused by a badly designed friction device that is part of the DBW system. This friction device is NOT used or needed in any non-DBW throttle system.

The problem with Toyotas is a direct result of them having DBW. It's a simple fact. Please accept it as such.

[dieselgeek]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

but in this case, nobody has com even close to showing that the problem here is worth blaming the "Drive-By-Wire" system.

The problem with Toyotas is a direct result of them having DBW. It's a simple fact. Please accept it as such.

sorry, but that's incorrect. The problem with Toyotas is a direct result of a badly engineered part. Engineered parts exist on BOTH types of throttle controls. Take it up with a Logic instructor if you disagree ???

[IRONHEAD]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

but in this case, nobody has com even close to showing that the problem here is worth blaming the "Drive-By-Wire" system.

The problem with Toyotas is a direct result of them having DBW. It's a simple fact. Please accept it as such.

sorry, but that's incorrect. The problem with Toyotas is a direct result of a badly engineered part. Engineered parts exist on BOTH types of throttle controls. Take it up with a Logic instructor if you disagree ???

after this mess the cable will be back in cars for the forseenable future..
as no one's gonna trust it.. no matter what they do to fix it

cable worked and any money they saved with these drive by wire just went up in smoke and then some..

[IRONHEAD]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

but in this case, nobody has com even close to showing that the problem here is worth blaming the "Drive-By-Wire" system.

The problem is caused by a badly designed friction device that is part of the DBW system. This friction device is NOT used or needed in any non-DBW throttle system.

The problem with Toyotas is a direct result of them having DBW. It's a simple fact. Please accept it as such.

x2

[squirrel]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

but in this case, nobody has com even close to showing that the problem here is worth blaming the "Drive-By-Wire" system.

The problem with Toyotas is a direct result of them having DBW. It's a simple fact. Please accept it as such.

sorry, but that's incorrect. The problem with Toyotas is a direct result of a badly engineered part. Engineered parts exist on BOTH types of throttle controls. Take it up with a Logic instructor if you disagree ???

Badly engineered parts can exist on both systems, yes.

But badly engineered parts that are INTENDED TO ADD FRICTION TO THE SYSTEM can only exist in the DBW systems.

This is a vital fact. If there is no damper in the system, then the damper cannot be designed badly, and the damper cannot fail.

The toyota case features a badly designed damper.

[IRONHEAD]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

wouldn't a spring under the pedal worked better.. and not be a wear item..
why is it they got to make stuff harder than it need be

[dieselgeek]

Re: Toyota Crisis Worsens, Cars Pulled From Rental Fleets, A Million More Cars Recalled

The toyota case features a badly designed damper.

And that's all that needs to be said, and that'sthe only "factual" point here. Badly designed part. Guess what? MANY recalls/lawsuits/deaths have resulted from "Badly Designed Part" since the dawn of automobile history. Trying to carry that out by saying "Toyota's problem is a result of Drive By Wire implementation" is NOT factual, or adding anything other than it's simply your OPINION that this problem wouldn't exist without going toDBW. When the fact is, this problem is a result of either bad engineering, or poor quality control, or anything else NOT related to electronic controls in the car. Toyota could have a HAND THROTTLE and still have a badly designed part cause the same kind of problem. Electronic controls are NOT the sole reason behind the problem, and that is fact.

Am I wrong here? I'll GLADLY accept being wrong if I am.