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

Vincent Keene · **Posted:** Thu Mar 04, 2010 12:44 pm

Chuck Branscomb wrote:

http://www.caranddriver.com/features/09q4/how_to_deal_with_unintended_acceleration-tech_dept

Duh!

Quote:

Hit the Brakes

Certainly the most natural reaction to a stuck-throttle emergency is to stomp on the brake pedal, possibly with both feet. And despite dramatic horsepower increases since C/D’s 1987 unintended-acceleration test of an Audi 5000, brakes by and large can still overpower and rein in an engine roaring under full throttle. With the Camry’s throttle pinned while going 70 mph, the brakes easily overcame all 268 horsepower straining against them and stopped the car in 190 feet—that’s a foot shorter than the performance of a Ford Taurus without any gas-pedal problems and just 16 feet longer than with the Camry’s throttle closed. From 100 mph, the stopping-distance differential was 88 feet—noticeable to be sure, but the car still slowed enthusiastically enough to impart a feeling of confidence. We also tried one go-for-broke run at 120 mph, and, even then, the car quickly decelerated to about 10 mph before the brakes got excessively hot and the car refused to decelerate any further. So even in the most extreme case, it should be possible to get a car’s speed down to a point where a resulting accident should be a low-speed and relatively minor event.

Richard Casto · **Posted:** Thu Mar 04, 2010 3:39 pm

Nice C&D article. I wish they had done some testing with pumping of the pedal to exhaust booster and see how that impacted braking distances.

steve remchak · **Posted:** Thu Mar 04, 2010 4:55 pm

Richard Casto wrote:

Nice C&D article. I wish they had done some testing with pumping of the pedal to exhaust booster and see how that impacted braking distances.

given that most if not all of these cars should have ABS, why would anyone pump the brake?

Vincent Keene · **Posted:** Thu Mar 04, 2010 5:53 pm

steve remchak wrote:

given that most if not all of these cars should have ABS, why would anyone pump the brake?

If none of these people had the good sense to even apply the brake, how would they have the presence of mind to pump it?

Richard Casto · **Posted:** Thu Mar 04, 2010 5:54 pm

steve remchak wrote:

Richard Casto wrote:

Nice C&D article. I wish they had done some testing with pumping of the pedal to exhaust booster and see how that impacted braking distances.

given that most if not all of these cars should have ABS, why would anyone pump the brake?

I would say that most people don't know how to use ABS and may even think something is wrong when ABS kicks in.

When people are in unfamiliar situations they do stupid things. I can clearly see someone tentatively pushing on the pedal and then releasing if it doesn't work as they expect right away. Then they might flash back to some advice someone gave them years ago about "pumping the brakes".

I think one of the first things people should do when they buy a new car is go out and simulate a panic stop somewhere to see just how the car feels/acts when it happens.

Donnie Barnes · **Posted:** Thu Mar 04, 2010 6:01 pm

steve remchak wrote:

Richard Casto wrote:

Nice C&D article. I wish they had done some testing with pumping of the pedal to exhaust booster and see how that impacted braking distances.

given that most if not all of these cars should have ABS, why would anyone pump the brake?

It's not about "pumping the brake", it's about the fact that people press the brake and think they've got it under control only to release it BEFORE they come to a stop. At that point the car starts taking off like crazy again and the theory is that you've now exhausted your boost pressure and now have MUCH less brake power available. I haven't tested that myself, but that's the theory, anyway (since the racing engine isn't creating any vacuum to speak of, so only that initial pressure in the system is available until the engine returns to more normal operating speeds).

I'm still having a tough time believing you won't have "enough" brakes to keep the car under control ENOUGH to figure out your next plan of action (neutral, turning it off, etc).

--Donnie

Richard Casto · **Posted:** Thu Mar 04, 2010 6:13 pm

Toyota clearly has some level of mechanical design issues that needs to be addressed. But I think a large part of the problem these days is that for most people cars have become an appliance. This means its is nothing more than a black box with buttons like "Start", "Go", "Stop" with no need to understand how and why it works.

Think back to the early days of personal computers. The early adopters were enthusiasts. The would have known everything about the computer from top to bottom. This results in knowledge that is not limited to "how to use" but also to "how it works". Computers are making the transition into the appliance category and most users these days don't know or care how they work. Cars are pretty much there now.

Outside of people like us who are car or motosport enthusiasts, I think that the majority of people don't really know (or car to know) how a car works. For me it's not uncommon to hear about people who don't know if their car is front or rear wheel drive. They may not know for sure if they have a four or six cylinder engine. So things like "gas" and "brake" pedals could just be labeled "go" and "stop" these days as I think most people just don't have a real clue as to how it all works.

I might try this sometime next week, but I would like to just survey some random people and ask them to explain to me...

* How an internal combustion engine works. (Bonus points if they can explain all four cycles of a traditional engine)
* How do brakes work. (Bonus points if they can explain how ABS works)
* How does a transmission work. (Bonus points if they can explain how gear ratios work)

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

Richard Casto wrote:

I would say that most people don't know how to use ABS and may even think something is wrong when ABS kicks in.

One of my students at the novice school last year was like this. She had never engaged the ABS. I told her "ok, for this last run, I want you to get into the brake so hard that the ABS pulses". "What?" "I want you to try and put your foot through the firewall." "Whats a firewall" "OK, just mash the brake REALLY hard".

It scared the hell out of her when it did kick in.

steve remchak · **Posted:** Thu Mar 04, 2010 7:32 pm

Richard Casto wrote:

I might try this sometime next week, but I would like to just survey some random people and ask them to explain to me...

* How an internal combustion engine works. (Bonus points if they can explain all four cycles of a traditional engine)
* How do brakes work. (Bonus points if they can explain how ABS works)
* How does a transmission work. (Bonus points if they can explain how gear ratios work)

ok, just don't ask me. :lol:

jakepressley · **Posted:** Fri Mar 05, 2010 1:29 pm

http://science.howstuffworks.com/engines-channel.htm

In my line of work, I often find myself in front of large groups talking about the hard and proven science behind forest management I've found that the advent of the internet, sites like the one I've provided the link to make people "instant experts."

Chuck Branscomb · **Posted:** Fri Mar 12, 2010 10:16 am

For those of us old dudes, I've been thinking about Audi a lot during this Toyota thing. WSJ just did a story about it today (nothing much to the article): http://online.wsj.com/article/SB10001424052748704349304575115952186305536.html?mod=WSJ_hps_LEFTWhatsNews

My son's 2001 S4 is definitely harder to heal-toe than it should be -- thanks to an extremely small segment of incompetent drivers here in the US 25 years ago.

60 minutes did the Audi story with fraudulent reporting. I assume we'll continue to see a good bit of that now with Toyota as the trial lawyers work on what they hope will be the biggest shakedown (where they take the vast majority of the money) of an auto company in history.

Sean O'Connell · **Posted:** Fri Mar 12, 2010 1:15 pm

has anyone seen this yet ?

http://www.toyota.com/recall/videos/...procedure.html

i find it hilarious yet sad that toyota has to make this.

ChrisSuich · **Posted:** Fri Mar 12, 2010 1:26 pm

Sean O'Connell wrote:

has anyone seen this yet ?

http://www.toyota.com/recall/videos/...procedure.html

i find it hilarious yet sad that toyota has to make this.

Bad link Sean

Chuck Branscomb · **Posted:** Fri Mar 12, 2010 2:15 pm

http://www.toyota.com/recall/videos/stopping-procedure.html

Keith Quistorff · **Posted:** Fri Mar 12, 2010 2:38 pm

Chuck Branscomb wrote:

http://www.toyota.com/recall/videos/stopping-procedure.html

Interesting they're recommending firmly braking with both feet along with putting the tranny in neutral.

Note to self - leave plenty of room when behind a Toyota.

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

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