Close up on Toyota/CTS gas pedal.

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Originally Posted By: wapacz
Originally Posted By: ShiningArcanine
This worries me because the video says that the issue is pre-mature wear. As far as my understanding of the english language is concerned, that means that the pedals were supposed to wear out and experience this issue at some point anyway, except at that point, the car would likely be out of warranty. That would mean that all drive by wire cars on the market could be ticking time bombs in terms of experiencing this.

At what point would mature wear cause this issue? Also, was this issue able to occur on vehicles that did not have drive by wire systems? Also, I heard that if you turn off your engine, you can steer your car to the side of the road, but you lose power steering when you do. I thought that with a drive by wire system, the steering wheel should not be mechanically connected to wheels, so if you turn the engine off, how can the wheels on the car turn when you turn the wheel?


In the Vernacular that we are using the drive by wire, we are talking about the throttle having no direct linkage to the gas pedal. I don't believe the government will ever allow a total drive by wire system in automobiles. By this I mean they will require brakes and steering to always have a mechanical linkage. So that in the case of total system electrical failure you can still use both.


That makes the notion of cars being drive by wire a misnomer. What is the benefit to doing it if you do not implement a complete system?
 
Used to see stuck open throttle all the time with rod linkages: broken motor mounts, loose carb and gasket misalignment, broken return springs. I bet the DBW ECT is more reliable than the old stuff - including cable throttles which have a limited life b4 they start binding. I work with BOSCH on automotive sensors for gschok and tpms and have maunfactured prototypes in the Boston area. I'd love to disassemble one of these ECT and perform a FMEA and CAPA. I would imagine a damaged polymer housing which would lead to a mispositioned hall sensor and effector which could bind, or a mislocated retirn spring. The housing could get damaged by someone pressing HARD on the pedal assy when putting on a seat belt, moving a seat or whatnot. I cant imagine an issue with the steel pin pivot in a sintered oilite bronze bushing giving any problems unless there was a fit issue due to damaged/dinged/cambered steel pin. All comes doem to good parts suppliers PPAP and QA - ask ford and chrysler about nice designs let down by shoody suppliers. Add in margin pricing constraints and an upper mgmt who can override QA stop shipment decisions to meet their shedule. Happenes to me all the time and gives me agita.
 
Originally Posted By: ShiningArcanine

Do old cars without drive by wire systems have parts that can wear out in such a way that they will accelerate out of control?


YES. The throttle cable can stick. I've also heard of situations where the motor mounts had worn out, and the engine pulled on the throttle cable as it moved (motion which the motor mounts largely prevent), causing it to rev up and the car to accelerate.
 
Originally Posted By: ShiningArcanine
That makes the notion of cars being drive by wire a misnomer. What is the benefit to doing it if you do not implement a complete system?
Well, TBW then. The benefit is that emissions are easier to control in transient conditions with an electronic throttle system. Remember dashpots on carburetors? That was an early method of modifying throttle behavior.
 
Having seen the video here.
And the pics on Edmunds.
The Denso unit seems to be sealed and built better.
We own one of each in our four car Koolaid fleet.
 
Well I was just reading the local paper and they where saying condensation was forming on the area and that the updated part they where making stopped this from happening.
 
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Originally Posted By: brianl703
Originally Posted By: ShiningArcanine

Do old cars without drive by wire systems have parts that can wear out in such a way that they will accelerate out of control?


YES. The throttle cable can stick. I've also heard of situations where the motor mounts had worn out, and the engine pulled on the throttle cable as it moved (motion which the motor mounts largely prevent), causing it to rev up and the car to accelerate.

Stuff like that could be pervented with some normal maintenance. Motor mounts wear out, Throttle cables get old.

This is all new stuff and no amount of maintenance could have prevented it.
 
Originally Posted By: Kiwi_ME
Originally Posted By: ShiningArcanine
That makes the notion of cars being drive by wire a misnomer. What is the benefit to doing it if you do not implement a complete system?


Well, TBW then. The benefit is that emissions are easier to control in transient conditions with an electronic throttle system. Remember dashpots on carburetors? That was an early method of modifying throttle behavior.


Also it allow for easier interactions of traction control system and stability control systems. In that it allows the computer to directly control the power output of the engine instead of only being able to lower the power output by pulling the timing. Then there are things like cruise control which can now be implemented with a few lines of code instead of a mechanical device.
 
Originally Posted By: ls1mike
Motor mounts wear out, Throttle cables get old.


A visual inspection will confirm a worn out motor mount, but how can you tell whether an asymptomatic throttle cable is worn out before it starts causing problems?
 
Originally Posted By: ARB1977
The traditional cable has worked since the modern vehicle was invented....why change.


I totally agree, while linkage activated components DO fail they are not anymore trouble prone than these more complicated electronic pieces....the reason WHY they changed is COST, COST, and COST...same goes for electronic servo steering....of course there are side effects with these NEW electrified items of all means from lack of steering feedback...

At least with cable actuated items you usually could EASILY pin point the source of trouble with these things NOT so easy...
 
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Originally Posted By: Pablo
An oil impregnated bush should be adequate. As he said the root cause remains unknown (to us).


+1 it could be a simple as a bad batch of bushings or a bad batch of the shafts that ride in the bushing. Or incorrect assembly procedure. Many possibilities.
 
Originally Posted By: ARB1977
The traditional cable has worked since the modern vehicle was invented....why change.


Horses still work...why change?
 
Originally Posted By: Vizzy

I totally agree, while linkage activated components DO fail they are not anymore trouble prone than these more complicated electronic pieces....the reason WHY they changed is COST, COST, and COST...


Just look at that throttle box, and the actuators on the butterflies.

You can't tell me that's cheaper than a few levels and a cable.

The reasons that they are removing the direct link from your foot to the butterfly have been mentioned in the thread.

Lets the computer more easily control things.
 
Originally Posted By: Shannow
Lets the computer more easily control things.

I'm not all that happy with that scenario either....time and time again TOO much computer intigration (at least at this point) in automotive products seems to lead to plenty of problems that are also not easily pinpointed or repaired....

I DO think that yes there can be a cost savings with certain electrical electronic applications even this.
 
Originally Posted By: PT1
Originally Posted By: ARB1977
The traditional cable has worked since the modern vehicle was invented....why change.


Horses still work...why change?


You have a point there. Horses also are less expensive than cars initially. I saw a show on TV where they were auctioning off horses for like $500 each, although I imagine the cost of feeding one would significantly increase its Total Cost of Ownership.
 
Originally Posted By: calvinnnnnnnnn
throttle cable > dbw
no lag and better for stick shift drivers



I almost forgot about that.....a huge issue with me as well.
 
Obviously a stupid way to make a gas pedal. It doesn't work well and has killed several people.
 
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