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Weirdest thing, a colleague had unintended acceleration in a Toyota 4WD of much older vintage, 80s or early 90s. Must have been something different entirely, th

Weirdest thing, a colleague had unintended acceleration in a Toyota 4WD of much older vintage, 80s or early 90s. Must have been something different entirely, those things were much more mechanical in nature.

btilly 7y ago
Most cases of unintended acceleration, in all brands of cars, are due to the foot coming down on the wrong pedal. And then in a panic, your brain refuses to acknowledge the error and doubles down. Your memory gets based on what your brain thought, and not what actually happened. US government estimates are that this happens an average of around 16k times per year in the USA. The press release that Wikipedia cites for that has disappeared but you can find it on the wayback machine: https://web.archive.org/web/20180423205652/https://www.nhtsa.gov/press-releases/nhtsa-safety-advisory-reducing-crashes-caused-pedal-error https://web.archive.org/web/20180423205652/https://www.nhtsa... Toyota's acknowledged problem was a floor mat that could get jammed and cause the accelerator to stick. However most of their cases of unintended acceleration were still likely to be human error.
- novaleaf 7y ago
  I'm sorry but you are wrong regarding the Toyota problem. There was (is?) a firmware issue that caused the vehicle to attempt to speed up, regardless of if the accelerator was pressed, or even if the brake was pressed. In my case, I had the brake fully depressed with around 100kg of force, and the engine was revving to attempt to overcome the brake (VERY scary situation, believe me!). The system only recovered when I bumped a taxi in front of me. Now you may say I was pushing the accelerator. If I did that I would have hit the car in front of me a lot faster than 5kph. If I was somehow pushing both the accelerator and the brake, the computer system should ignore the acceleration anyway (due to brake taking precedence). But you don't have to take my word for it. Go read up on the Toyota firmware issue, starting with link I put in the prior post. EDIT: here's another article, summarizing the faults as determined by court: https://www.edn.com/design/automotive/4423428/Toyota-s-killer-firmware--Bad-design-and-its-consequences https://www.edn.com/design/automotive/4423428/Toyota-s-kille... - Toyota’s electronic throttle control system (ETCS) source code is of unreasonable quality. - Toyota’s source code is defective and contains bugs, including bugs that can cause unintended acceleration (UA). - Code-quality metrics predict presence of additional bugs. - Toyota’s fail safes are defective and inadequate (referring to them as a “house of cards” safety architecture). - Misbehaviors of Toyota’s ETCS are a cause of UA.
  - maimeowmeow 7y ago
    maybe you were pressing both
    - novaleaf 7y ago
      From what I understand, the computer will (and should) reject the acceleration attempt in favor of the brake. But, if you own a reasonably modern vehicle, try it :)
      - gavia1 7y ago
        If this were true people wouldn't be able to do burnouts in auto transmissions cars?
        ihattendorf 7y ago
        It's actually fairly common, try searching for "brake override".
      - gburdell3 7y ago
        That's not how it works. The brakes are more powerful than the engine, sure, but only at full braking power. Ask anyone who owns a rear-wheel-drive sports car what happens when you push both pedals at the same time and they will literally leave you in a cloud of smoke.
        Arbalest 7y ago
        The RWD thing is definitely important here. Given that the majority of cars and a significant number of SUVs are now FWD, this doesn't hold water. Given it is the front brakes that are more powerful than the rears, and if your brakes are maybe a tad worn out, you might not be able to take your brakes from a dynamic friction situation to a static friction situation. In the mean time, your engine would just continue injecting heat into the brakes, which could easily overcome them. It might also be that he was not braking with the full force initially, meaning some degree of heat saturation may have already been present.
mattdanger 7y ago
Cars of that vintage still had cable operated throttle bodies which could stick for a number of reasons.
abawany 7y ago
Often badly-placed floormats could also cause this issue. I remember a few automaker recalls in the prior decade that comprised of adding hooks to the floor boards to avoid floormat movement.

btilly 7y ago

Most cases of unintended acceleration, in all brands of cars, are due to the foot coming down on the wrong pedal. And then in a panic, your brain refuses to acknowledge the error and doubles down. Your memory gets based on what your brain thought, and not what actually happened. US government estimates are that this happens an average of around 16k times per year in the USA. The press release that Wikipedia cites for that has disappeared but you can find it on the wayback machine: https://web.archive.org/web/20180423205652/https://www.nhtsa.gov/press-releases/nhtsa-safety-advisory-reducing-crashes-caused-pedal-error https://web.archive.org/web/20180423205652/https://www.nhtsa... Toyota's acknowledged problem was a floor mat that could get jammed and cause the accelerator to stick. However most of their cases of unintended acceleration were still likely to be human error.

novaleaf 7y ago
I'm sorry but you are wrong regarding the Toyota problem. There was (is?) a firmware issue that caused the vehicle to attempt to speed up, regardless of if the accelerator was pressed, or even if the brake was pressed. In my case, I had the brake fully depressed with around 100kg of force, and the engine was revving to attempt to overcome the brake (VERY scary situation, believe me!). The system only recovered when I bumped a taxi in front of me. Now you may say I was pushing the accelerator. If I did that I would have hit the car in front of me a lot faster than 5kph. If I was somehow pushing both the accelerator and the brake, the computer system should ignore the acceleration anyway (due to brake taking precedence). But you don't have to take my word for it. Go read up on the Toyota firmware issue, starting with link I put in the prior post. EDIT: here's another article, summarizing the faults as determined by court: https://www.edn.com/design/automotive/4423428/Toyota-s-killer-firmware--Bad-design-and-its-consequences https://www.edn.com/design/automotive/4423428/Toyota-s-kille... - Toyota’s electronic throttle control system (ETCS) source code is of unreasonable quality. - Toyota’s source code is defective and contains bugs, including bugs that can cause unintended acceleration (UA). - Code-quality metrics predict presence of additional bugs. - Toyota’s fail safes are defective and inadequate (referring to them as a “house of cards” safety architecture). - Misbehaviors of Toyota’s ETCS are a cause of UA.
- maimeowmeow 7y ago
  maybe you were pressing both
  - novaleaf 7y ago
    From what I understand, the computer will (and should) reject the acceleration attempt in favor of the brake. But, if you own a reasonably modern vehicle, try it :)
    - gavia1 7y ago
      If this were true people wouldn't be able to do burnouts in auto transmissions cars?
      - ihattendorf 7y ago
        It's actually fairly common, try searching for "brake override".
    - gburdell3 7y ago
      That's not how it works. The brakes are more powerful than the engine, sure, but only at full braking power. Ask anyone who owns a rear-wheel-drive sports car what happens when you push both pedals at the same time and they will literally leave you in a cloud of smoke.
      - Arbalest 7y ago
        The RWD thing is definitely important here. Given that the majority of cars and a significant number of SUVs are now FWD, this doesn't hold water. Given it is the front brakes that are more powerful than the rears, and if your brakes are maybe a tad worn out, you might not be able to take your brakes from a dynamic friction situation to a static friction situation. In the mean time, your engine would just continue injecting heat into the brakes, which could easily overcome them. It might also be that he was not braking with the full force initially, meaning some degree of heat saturation may have already been present.

mattdanger 7y ago

Cars of that vintage still had cable operated throttle bodies which could stick for a number of reasons.

abawany 7y ago

Often badly-placed floormats could also cause this issue. I remember a few automaker recalls in the prior decade that comprised of adding hooks to the floor boards to avoid floormat movement.