[RHSeeger]

Many years ago, I was driving down the highway on my way to work and, when I pressed the breaks to slow down, the pedal just... went straight to the floor. I had to use the emergency break to slow down, get off the highway, and pull over. Luckily that still worked (I've owned many a car where that was the first thing to go).

So, it turns out the breaks rotted off and fell off the car on the way to work. I had had it inspected the previous day... and they didn't mention anything was wrong. I did not go back to that inspection place again.

[technothrasher]

When I was first dating my wife, I think it was our second date, she was driving a ratty old 82 SAAB 900 that her dad had handed down to her. While she was coming to a stop at a light, the brakes failed on her and she panicked. I reached over and pulled the emergency brake (luckily on the transmission tunnel and not by the driver's door in that car), and we stopped in time to just barely kiss the rear bumper of the car in front of us. The driver looked in his rear view mirror with a "WTF?" expression and I sheepishly mouthed "sorry". She made me drive the car back to her house on the emergency brake, as she was too scared. I then diagnosed it as the master cylinder, went to the auto parts store that afternoon and bought a new one, installed it and bled the brakes, and got her back on the road. She says now that was when she decided I might be worth marrying, but that she foolishly didn't realize that I came as a package deal with an unending string of "old ugly smelly sports cars".

[fallinditch]

Wow you were lucky. There was a driver in the UK whose accelerator got stuck, then his brakes burnt out and he was on a notoriously busy road traveling at 135mph - he survived! See https://www.the-independent.com/news/uk/this-britain/help-i-...

[wat10000]

This is what happened to quite a few people with the Toyota unintended acceleration issue. There was speculation that it was caused by bugs in the engine control unit. Officially the cause was found to be floor mats coming loose and holding the accelerator down. (I bought a new Toyota shortly after this and the dealer was very careful to show me how the floor mats worked and how to make sure they were properly attached.)

The brakes of a car in good working order should be able to overcome the engine and stop the car even if the engine is stuck at full power. But you have to do it decisively. Push the brake pedal to the floor and keep it there until you've stopped. What often happens is people are (very naturally) confused and not sure what to do, they'll brake but not hard enough, stop braking when it doesn't seem to work, try again, etc. This can heat up the brakes to the point where they're no longer effective enough to stop the car, and then you're really in for it.

[red369]

I agree with what you said about brakes overcoming the engine. I've seen tests which show it works on even monstrously over-powered cars, but it can feel like it's not working and if the driver reacts wrongly to that, then it may no longer work.

I think stopping the power from going to the wheels needs to be an easy option. I wish there was more importance given to being able to easily do this.

I think the two options are shifting to neutral, or turning off the engine. I tested in a late-00s automatic BMW, and you had to hold the start/stop button for what felt like a very long time to turn the engine off if the car was in Drive. In an emergency, I think most people would give up long before it turned off. In that car, it was easy to change to neutral though, so I don't have a criticism about that design. What concerns me is cars with the same approach for the start/stop button, but where it is hard to get to neutral. I think in the Toyotas which had unintended acceleration issues, it wasn't easy/intuitive.

Edit: Another comment reminded me of something I forgot to mention above. You don't want turning off the engine to be the first resort because you lose power steering, and eventually, power assisted brakes.

[red369]

I was with a friend in a 5L V8 Mercedes, and we were doing a quick drive around the block after some sort of maintenance. He floored the accelerator - I can't remember why that was required, except I assume it wasn't. I assumed he was only going to do it momentarily, but the car rapidly reached, and passed, stupid speeds for that road. Just as I started to say something about preserving lives of us, and anyone else on the road, he suddenly shifted to neutral and brought the car to a stop with the engine screaming away at the redline. He then calmly reached down, unjammed the accelerator, and then continued driving back home.

That car was automatic, but he drove cars with manual transmissions a lot, so that would make it an obvious thing to do. I think in some of the famous unintended acceleration crashes, it has been unclear whether the person tried to change to neutral. A lot of newer cars have a much less intuitive method of doing so as well.

There's nothing as good in this regard as cars with manual transmissions though, in terms of having a dedicated pedal which disconnects the engine from the wheels, which you practice constantly during daily use.

[toast0]

Seems like he wasn't able to get it out of gear, and then didn't want to turn off the engine because he'd lose power steering. Losing power steering isn't ideal, but seems like it'd be better than traveling at 135 mph, power steering is most important at low speeds, and I'd think better to have a bit of trouble with the steering as you get it stopped than to end up crashing it.

[HeyLaughingBoy]

Not only did this happen to me (caused by a hole in a brake line), it occurred the week after I happened to take the time to fix the emergency brake that hadn't worked in years. But yet I have no luck at the casino!