Slashdot discussion of "sudden acceleration"

I can tell you that, from my 8-year tenure as a service writer, if a DBW system detects any anomalies in any redundnacies with itself, the engine will not come off of idle. No amount of gas pedal application will change that.

 

ABC Nightline Segment, 11/03/09

 

This reminded me os a TV show I seen on FOX a LOOOONG time ago about cars going crazy. It was something about the CAT that made the cars crazy. When the CAT was removed or something the car would crash straight into a wall then reverse into another wall then drive forward again into the wall. They would spin out and flip over. It was all FUD to try to get rid of the things or something. I dont remember the name of the show.


This "Toyota problem" is going to be 1 of two things.

1. Its a real problem. Its going to be like one of those very rare computer problems that you just cannot replicate over and over again to find the cause. Stuff like that usually never gets fixed because it so hard to find the problem.

2. This is all FUD to make Toyota look bad and to get people to buy American.

 

Everything old is new again. It was driver error in the '80s with Audi and I'm supremely confident it will end up being that now.

(Edit: Was it ABC which started the Audi 5000 witchhunt or was that CBS?)

 

I came here to say just that - Spot On!

-Brad

 

For the accelerator rebuilding project Doug lets me carry forward:

Accelerator Experiment

Comparison of NHW11 and NHW20 accelerators:


Example of the NHW11 performance after repair:


This was from a unit with a 'bent' cam follower:


Before and after contact cleaning:



One accelerator that had a bent cam follower:


Unit has been repaired but it part of my experimental set:


Accelerator test jig:


Bob Wilson

 

Actually the Audi fiasco was found to be caused by driver error induced by having the throttle and brake too close together. So it was an ergonomic problem.

I suspect the "Toyota problem" is caused by people, period. I have never, and never expect to, have a problem with "sudden acceleration", brake failure, the car accelerating suddenly during braking, or any other small brain induced or imagined failure.

The Prius is a computer system. The operator has absolute control. If the car isn't doing what you want, you can always shut it down (hold power switch down for 3 sec. - just like -any- computer made will do and has done for the last 15+ years.

So "hey bud, what's your problem"?

 

Not to argue, but I don't think the Audi "problem" was ever resolved. I believe the most logical conclusion was that the brake pedal and gas pedal were is a slightly different position than most cars, but I don't think it was ever "proved". I believe the problem went away on it's own as there was never one to begin with, but not before absolutely trashing the re-sale value of an Audi first.

 

At the risk of being accused of :tinfoil3:, I would suggest that Toyota's "sudden acceleration problem" has a lot more to do with GM's sales numbers than it does with Toyota's cars.

 

I can't remember in which magazine I read it years ago (Automobile or Car & Driver) where they put unsuspecting people in different cars (including a 5000 Avant) to get their impressions on subjective concerns. At random times, they could trigger a "blip" in the Audi's throttle to see what the driver would do. Typically this was done while the driver was performing an "agility and visibility" test by doing a reverse slalom through a set of cones.

Unfailingly, the drivers would attest they had the brake pedal all the way to the floor and, unfailingly, photo evidence showed the brake lights were unequivocally off. Sure, there may have been ergonomic issues which predisposed the vehicle to pedal misapplication. However, at the end of the day, it was driver error at the root of the cause and not some demonic possession which caused the 5000 to rocket off into the pachysandra at breakneck speeds, mowing down small children on tricycles and the elderly crossing the street with their walkers in the process.

 

Not related to the floor mat thing, but I've noticed when the car is warming up that there is a slight surge acceleration at about 20mph. I have only noticed it twice and it's only slight, say 1mph, but disconcerting.

 

If there really is a problem with the Prius drive-by-wire throttle, we're in deep doo-doo. Almost every new vehicle on the road now, foreign and domestic, uses drive-by-wire throttle and CANBus. The newest cars use FlexRay, an evolution of CANBus

I have no doubt that out of hundreds of thousands, or perhaps a million vehicles, a handful won't have some sort of glitch. Nobody can guarantee anything to be 100%

In that context, until it happens to you, runaway cars are a statistical oddity. Thanks to the (lack of) driver training these days, nobody knows how to change a flat tire, operate a stick shift, properly park on a hill (Hint: wheels turned IN or OUT?), or shift a transmission into neutral

I've had direct personal experience with a WOT runaway, but that was around 25 years ago. I helped a buddy rebuild a 350 V8 to put into a '69 Chevy C10 pickup, which had originally come with a 327

To save money, he reused a lot of parts, especially the carb return spring. Everything went together fine, fired right up, we then took it out on an isolated road to break it in

He hit the pedal a little harder, and suddenly all four barrels were wide open. He shifted into N, killed the ignition (Flooded the engine too, as the carb was still wide open), and we coasted to a stop in the rich smell of gasoline

The return spring had broken right by hook which goes onto the carb throttle lever. I held the carb wide open while he cranked it. When it finally fired, I snapped the throttle closed, then we turned around and slowly putted back to his place. Easy solution: new return spring

The other experience wasn't as dramatic. The Ford work truck at my hobby farm uses a throttle cable. After +20 years, it became frayed and would sometimes stick at around 1/3 pedal. The solution was simple: a new throttle cable

 

And if there isn't, which is much more likely give the fact that no such problem has EVER been demonstrated, this whole thing is just a few jammed floor mats, a few bad drivers, and a whole lot of media scaremongering to drum up ratings... result of which will be that Toyota will get an unearned bad rep, the resale value of our cars will be destroyed, future models will be crippled somehow, and a whole bunch of unscrupulous lawyers will get rich.

 

This story sounds familiar. Hmm, oh yea, now I remember: silicone breast implants - huge media uproar, people screaming, lawyers and big class action suites, companies bankrupted, all without scientific evidence. When the evidence did come in, it vindicated the now bankrupt companies, not that it did them any good.

Tom

 

Seems to be a common thread doesn't it?

 

I had this happen to me the other day....it scared me a little. I was coming to a stop over some rippled pavement on a downward slope and I noticed the CHG section of the display bar was lighting up and then the car surged forward for just a second with very little break control. If there was someone in front of me it would have been a hit. Be very careful slowing down on rippled pavement!

 

This issue has been addressed many times on several other threads. The short answer is that your Prius didn't "surge forward". What actually happened is a loss of braking traction which caused a transition to ABS braking. The momentary reduction in braking effort feels like a surge forward, but it isn't. At no time did your Prius gain speed. In fact it was slowing down the whole time.

Tom

 

I wish I could disagree with this but experience says you are spot on.