Unintended acceleration

[Barklessdog]

We have an 08 Highlander that is not part of the recall (J series- japanese built part)

Saw this video on the highlander site. How many people do not think to shift the car in neutral?
People have died not doing that.

http://www.youtube.com/watch?v=FT07_JbnKWQ&feature=player_embedded

The scary part is that if you pump the brakes it disables them!

German cars brakes override the accelerator - seems like comon sense?

[Pilgrim]

All cars with vacuum or hydraulic assist (Audi is hydraulic) lose power as the brake is repeatedly applied - the vacuum or hydraulic pressure is used up (reduced) with each application.

A stout application of the brakes should not deplete properly functioning assist with one application....but pump them like crazy (most likely panic response) and you can probably deplete vacuum assist faster than it regenerates even with the engine running. 

I'll wager that does NOT happen with the type 44 Audi (1984-91 5000, 100, 200) series, which run 2400 PSI of hydraulic assist.  It takes about 20 applications of the pedal to deplete the reserve pressure.

But shifting into neutral - requires thought, doesn't it?  I'll bet the thought would occur more readily to those who also drive stick transmissions.

I once had the throttle return spring fall off the carb linkage in a '66 GTO while I was passing another car on a Idaho mountain road.  My 2-3 shift was a power shift to be remembered as the gas pedal stayed down...probably laid rubber for 10 feet.  The next corner was approaching rapidly until I got my toe under the brake pedal and pulled it up.  I used the gas pedal like a cruise control for the next few miles (set it and let it cruise) until I got to a spot where I could pull over.

[Hornisse]

A guy here in Austin just last week wrecked his Grandparents 2007 Avalon.  He was making a right turn when the car accelerated and he lost control and hit a light post.  I his case I think it happened so quickly he did not have a chance to put it in neutral, as you would say driving a long straight stretch of highway. 

My 1994 Toyota truck is safe as I have a 5 speed manual. 

[jmcgliss]

I suppose there are people who expect that something like OnStar will take over for the driver to turn the engine off, or that the auto industry requires more regulation. Is this any different from the accidents that happened when people were surprised by adjustable mortgage rate re-sets (unintended amortization)? Sometimes life requires thinking ahead just a bit, and assuming some responisbility.

At track events we coach people to be very aware of traffic, closing speeds, and runoff areas if something goes wrong, as well as how to minimize a crash.  I would venture that most street drivers just assume nothing can ever happen (mechanical or human)...but what's up with the rollover accidents during rush hour? And yet Toyota's floormats and pedals get this much attention as if it's the only factor that causes accidents. Call it Media Unintended Distortion.

[Pilgrim]

What gets me is that NO vehicle - especially a passenger vehicle - can overpower its brakes.

If you floor the throttle and simultaneously stomp the brakes, what happens?

YOU STOP.  Maybe not instantly, but pretty darn soon.

If this is not the case, the brakes on the vehicle are obviously unsafe and inadequate for the vehicle.

I can certainly understand how if a throttle stuck wide open while turning a corner or in a situation where one is in traffic and has only moments to respond.  But I can't see any situation that goes on for more than 10-15 seconds concluding any other way than with the vehicle stopped.

[Grog]

These cars that have this problem, use a "Throttle by wire" setup instead of throttle linkage. My 2000 Tundra was one of the first Toyota's to utilize this technology. It uses a potentiometer & a senser. The news flashed CTS for a brief moment as being the supplier in question. Maybe your Gibson & your car have simillar parts.............

[Pilgrim]

Even with throttle by wire, if the brakes cannot stop the car while it's under full throttle, then I contend something is wrong with the design of the braking system.

[Pilgrim]

I learned moer about the Toyota situation - evidently when the throttle sticks, in at least some cases the brakes will not work.

It's not clear to me whether this is because the floor mats bunch up so badly that the brake pedal can't be depressed, or whether there is some cascading mechanical problem....but that's absolutely not acceptable.

This is one reason that for years, I've tried to always check the floor mat on the driver's side when i get into a car.  I do really well at it when it's an unfamilar car - not so well when it's one I drive every day.

[jmcgliss]

What happens to the brakes is that wide-open-throttle, coupled with the panic reaction to pump the brakes, depletes the vacuum booster. Standing on the brake pedal and keeping it there would probably not deplete vacuum, but very few drivers (maybe 1%-3%) have a motorsports perspective that would result in applying enough brake pressure immediately.

[Pilgrim]

What happens to the brakes is that wide-open-throttle, coupled with the panic reaction to pump the brakes, depletes the vacuum booster. Standing on the brake pedal and keeping it there would probably not deplete vacuum, but very few drivers (maybe 1%-3%) have a motorsports perspective that would result in applying enough brake pressure immediately.

I think you're right - and at WO throttle, vacuum is at its lowest so it wouldn't replenish the booster as fast.  (Anyone who has driven an older car with vacuum wipers knows how vacuum drops off when you accelerate.)

[Denis]

I contend that the floormat fiasco is and always was a smokescreen intended to cover up the real problem. A couple of weeks ago they attributed the sudden acceleration to "moisture and dirt" buildup in the linkage assembly". They claim a metal rod will fix that problem but I have my doubts.

Regarding the Pruis, Toyota says now that it has fixed the models sold in the last couple of months, but "is figuring out how to notify purchasers of the cars before January, 2010". Uh, how about a recall notice? This is not rocket science nor is it something which has never happened to other manufacturers, so Toyota's inability to do what's right mystifies me, unless they've gotten big heads from their success and think they can shove their way through this like the US manufacturers used to do.

When I learned to drive we were always told to pump the brakes (and on old drum brake cars like my Dodges, Galaxies, Studebakers, etc) but with the invention and common application of antilock brakes constant and firm pressure is what's needed. Maybe a lot of people still don't realize that.

One of the front brake lines blew out on my '66 Polara and since it was a single reservoir master cylinder I had nothing left in that department. So I pulled the emergency brake handle and used that brake to slow the car so I could get it down into first gear. This happened while I was going into a sharp turn on an exit ramp with a stop sign at the top. And no, I wasn't able to stop at the sign. Point is, there was something I could do.

Could any of these folks simply turned the ignition switch off?

[Dave W]

On the news last night they showed the repair parts Toyota will use, they look like fairly thick metal shims. I wonder if it will really eliminate the problem.

[Denis]

Oh, now they say shims will do the trick? I really think they are panicking and have no idea what to do.

[jmcgliss]

The shim will prevent a stray Starbucks lid from getting jammed under the pedal   

[Denis]

The shim will prevent a stray Starbucks lid from getting jammed under the pedal   

I avoid that problem by drinking my boiling hot coffee out of open-topped mugs while driving...