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UPDATE: you're up to 100 mph, would you kill the engine, or shift into neutral?


LarryC

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My MINI has both a rev limiter and a top speed limiter (which is less than theoretical max speed at rev limit). I also had no problem braking at full throttle on interstate in 6th or 5th gear but as there is an electronic throttle Mr. Computer may have been helping by pulling back the throttle.

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I have an older Ford F-250 diesel pickup (1992) that we use occasionally drive on the weekends. One day, while driving down the highway, the gas pedal suddenly went down the floor on it's own. While I was accelerating to about 70mph, I panicked. I reached down and tried pulling up the pedal. Didn't work... I litterally stood on the brakes, which slowed me down enough to pull on the shoulder and put it in neutral.. Why didn't I just put it in neutral in the first place is beyond me.. I was approaching a 3 way intersection and it just happened so fast. Alot of things go though mind when in panick mode.. After it happned, I unhooked the cruise control and have never had it happen to me again...

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I guess I have been lucky...Cos my 1965 Toyota Corona has never had no problem with its computer or rev limiter.Big Smile

I did get it to 90mph one time and it complained a little.

Got my 70 beetle near 90 and it never complained.

Yeah but my speedo was accurate.....[;)]
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I litterally stood on the brakes, which slowed me down enough to pull on the shoulder and put it in neutral.. Why didn't I just put it in neutral in the first place is beyond me.. I was approaching a 3 way intersection and it just happened so fast. Alot of things go though mind when in panick mode..

And I think that would be my very first impulse -- I've never had an engine rev high, and probably would panic just to get the revs down. That's why I'm afraid the unexpected hi-rev sound would KO any calm, cool, intellectual approach, and I'd reach for the ignition (if a key ignition) and then only start to think after the P/S and P/B suddenly stopped working.

I suspect that would be most people's reaction, anyway.

I think car makers should not switch to computerized ignition without adding Smart Throttle at the same time.

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I think car makers should not switch to computerized ignition without adding Smart Throttle at the same time.


Those Engine Start/Stop buttons are just an unnecessary frill to give the impression that the car is more cool or more highly engineered, just like the separate instrument light rheostat.

Engine On and Engine Start/Stop in a single key control and Headlights/Instrument Lights in a single control worked well and reduced dashboard clutter, but I guess some marketing guy thought those simple controls were old-fashioned and asked for more controls to do the same job, in order to impress easily-impressed buyers.
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I think car makers should not switch to computerized ignition without adding Smart Throttle at the same time.


Those Engine Start/Stop buttons are just an unnecessary frill to give the impression that the car is more cool or more highly engineered, just like the separate instrument light rheostat.

Engine On and Engine Start/Stop in a single key control and Headlights/Instrument Lights in a single control worked well and reduced dashboard clutter, but I guess some marketing guy thought those simple controls were old-fashioned and asked for more controls to do the same job, in order to impress easily-impressed buyers.
I don't know that computer engine management is related to start/stop buttons.

Aside from that, I agree with you if you still have to insert a key. In that case, a button is an unnecessary second step to start the car, instead of a single insert-and-twist key start system.

However, a "keyless go" system removes the need to insert a key. In that case, a simple button push starts the car (you have to be in the driver's seat and step on the brakes). My button sits right on top of the auto transmission selector, which is extremely convenient for both starting and stopping the engine. I don't have to reach to the dash for a button or a key.

The only problem is I sometimes forget that I don't have to push that button to shift out of park, and kill the engine!

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As a 17 y/o my first car was a shared venture with my best friend. We each pitched in $125 and bought a ragged out 1960 Austin-Healy 3000. A thing of beauty, yes, but ruled by Lucas, Prince of Darkness.

Anyway, I'm headed downhill on the one-way, 3-lane 2nd street at about 40mph, approaching the light at the bottom of the hill. I apply the brakes and *SNAP* the linkage breaks. I try the emergency brake. Nothing. I try downshifting but those old trannies were NOT synchro, 'cept in 1st. No go. There is no shoulder, high curbs on each side, and the street is lined with large, closely-spaced elms. Oh, the light is red and a car in each lane. I'm hosed.

At the last second, I yanked the steering wheel hard right, trying to make a driveway, which I mostly missed, whipped left again, and went bouncing and crashing along the sidewalk parallel to the street. The car rolled to a stop just inches from the stop light at the corner. My friend, the co-owner, who has been silent up to now, looks over and shouts "VERY FUNNY!" He didn't know the brake cable broke. LOL!

I doubt my reactions today match mine of yore, but I like to think I'd act appropriately in an emergency as above.

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There was later fallout from this incidient, brought on by the violence of hopping those high curbs at speed. Mark was tooling about town, minding his own business when he drove over a sharp bump. Both rear leaf springs cracked through and the body fell onto the rear wheels resulting in huge clouds of gray-blue tire smoke until Mark could wrestle the poor thing to a stop.

This, on top of constantly having to deal with Evil Sir Lucas, killed the car. Off to the crusher you go.

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There was later fallout from this incidient, brought on by the violence of hopping those high curbs at speed. Mark was tooling about town, minding his own business when he drove over a sharp bump. Both rear leaf springs cracked through and the body fell onto the rear wheels resulting in huge clouds of gray-blue tire smoke until Mark could wrestle the poor thing to a stop.

This, on top of constantly having to deal with Evil Sir Lucas, killed the car. Off to the crusher you go.

Sounds like another quality minded Mopar incident.

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Some Toyota and Lexus owners have suddenly found their vehicles in runaway acceleration to near-maximum speeds, and there've been a number of fatalities and serious injuries. See last night's ABC News report, and be sure to run the video report: http://abcnews.go.com/Blotter/RunawayToyotas/sudden-acceleration-toyota-cars-owners-rebel-accidents/story?id=8980479. See also http://www.theautoindustrieblog.com/2009/10/lexus-lacks-critical-safety-feature-for.html

As noted, Toyota has tried to blame it on driver error and incorrectly-sized floor mats catching and holding down the gas pedal; it has initiated a recall of 3.8 million drivers' floor mats. Some owners are now angry at Toyota, saying that's not it, but something else such as its engine-management computer. Toyota is (very!) reluctantly looking at that, too. I know Lexus can get stuck in arrogance and denial over the supposed perfection of its cars.

A possible runaway acceleration problem has plagued some cars in the past, such as Audi. Interestingly, makers' philosophies seem to vary by country! This NYT article and comments only a month ago summarizes the "Smart Gas Pedal" solution: http://wheels.blogs.nytimes.com/2009/10/07/smart-gas-pedals-may-solve-floor-mat-problem/ With this system, applying brakes and gas at the same time DEACTIVATES THE GAS PEDAL. This system has been installed on mostly German cars -- Audi and VW since 2001 and BMW since 2005. Mercedes also has it.

In contrast, Japanese cars DO NOT use this system, except Nissan will put it on Infinitis in 2010. The U.S. as usual is also way behind the curve, except Chrysler (because owned by Daimler?). The system really works: http://blogs.consumerreports.org/cars/2009/10/toyota-recall-putting-stuck-floor-mat-survival-strategies-to-the-test.html.

Now, what do YOU do if you get caught in this situation? I'll bet, with a madly racing engine, a sense of panic, and an inability to slow the car much with the brakes, you'd try turning off the engine. That'd be my response, too! Unfortunately, that will kill the power brakes and power steering, and if you turn the key too far, it would lock the steering!

The proper way would be to put it in neutral, even though the engine will really rev, and bring the car to a stop BEFORE shutting off the engine. http://blogs.consumerreports.org/cars/2009/10/putting-a-car-in-neutral-might-save-your-life.html. Unless, of course, you have a car with a smart throttle.

I'm still not sure I'd do it right....

There is so much idiocy here it's hard to know where to start.

All decent cars will stop from 60 MPH in <125 feet, now, that's got to be about 3 seconds. How long does it take a big Toyota to accelerate to 60? 9 or 10 seconds? Since the weight is the same and the time is less, the brakes' power FAR exceeds the engine's power. The engine CANNOT OVERPOWER the brakes. Panic and hysteria notwithstanding.

Next, if the ECU were to call for full throttle in a drive-by-wire system AND you diddled with the brakes enough to deplete the vacuum in the booster, turning off the engine will have no effect on the brakes' power. If you haven't depleted the vacuum, killing the engine will not deplete the vacuum and the brakes will have normal power. So,...... KILL THE ENGINE. Power steering is not as critical as power brakes, you can still steer the car.

We wouldn't have this exact problem if we had cable controlled throttles.

Audi's "problem" was driver's mistaking the brake and throttle because they built them at the same height off the floor; a European thing.

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As was pointed out in the above articles, hit the brakes twice at WOT and the vacumn is depleted. Without power assist, the engine easily overpowers the brakes.

It has always taken 3 or 4 applications of the brake to deplete the vacuum without the engine running (worse than WOT) in all the cars I've had. I'll try my truck tomorrow.

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Turning the engine off with a stuck throttle with fuel injection could possibly hydraulic the engine!!

Doesn't take alot of thought here, just some basic understanding of how an engine works!!

Roger

NOPE! Killing the power to kill the engine, shuts off the power to the fuel pump and the injectors. Hydrolocking the engine is NOT possible.

If the ECU malfunctions enough to hold the throttle open, why would you believe the rev limiter will still work?

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I guess I have been lucky...Cos my 1965 Toyota Corona has never had no problem with its computer or rev limiter.Big Smile

I did get it to 90mph one time and it complained a little.

Got my 70 beetle near 90 and it never complained.

Yeah but my speedo was accurate.....Wink

Oldenough,

I'd watch those VW comments if I were you..... Kevin Harmons son has a built up VW as well as two of his three brothers. His first younger brother Damon Harmon owns the worlds fastest Pro Stock VW Bug!! Damon has two Pro Stock VW Bugs that run deep in the 9s (9.52 @139mph) in the quarter mile. That's Pro Stock, built up 4 cylinder Bug type air cooled engines with no power adder!! No nitrous, no turbo, all motor. You want to talk a big satchel, his one bug weighs in at 1800 pounds with him and fuel in it, and runs a 1.30 60 foot time, he turned a 1.29 once. Now think about a cross wind on the big end of the track with that much side area and no weight, and I'd much rather be on a 9 second bike!!

Roger

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Turning the engine off with a stuck throttle with fuel injection could possibly hydraulic the engine!!

Doesn't take alot of thought here, just some basic understanding of how an engine works!!

Roger

NOPE! Killing the power to kill the engine, shuts off the power to the fuel pump and the injectors. Hydrolocking the engine is NOT possible.

If the ECU malfunctions enough to hold the throttle open, why would you believe the rev limiter will still work?

John,

You are correct, all my experience is with mechanical fuel injection, and that is where my head was. Hydraulicing the engine with mechanical injection is most certainly possible with extremely high base compresssion, or enough static compression in a boosted aplication, as well as killing the ignition on a big enough hit of nitrous with big compression.

Roger

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Turning the engine off with a stuck throttle with fuel injection could possibly hydraulic the engine!!

Doesn't take alot of thought here, just some basic understanding of how an engine works!!

Roger

NOPE! Killing the power to kill the engine, shuts off the power to the fuel pump and the injectors. Hydrolocking the engine is NOT possible.

If the ECU malfunctions enough to hold the throttle open, why would you believe the rev limiter will still work?

It's probably in the cruise control, so why would you automatically think the rev limiter would not work, it is a seperate circuit, but again, I was thinking in terms of mechanical orriginally. Last I knew, BDS electronic hats were still full of bugs and nobody was making an electronic settup capable of 1,400 horsepower or electronic injectors capable of the fuel flow requirenments. 1,000 horsepower yes, but not alot over that, and these are still in the custom build category by far, not bolt on.

Roger

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It's probably in the cruise control, so why would you automatically think the rev limiter would not work, it is a seperate circuit, but again, I was thinking in terms of mechanical orriginally. Last I knew, BDS electronic hats were still full of bugs and nobody was making an electronic settup capable of 1,400 horsepower or electronic injectors capable of the fuel flow requirenments. 1,000 horsepower yes, but not alot over that, and these are still in the custom build category by far, not bolt on.

Roger

Because the ECU also runs the cruise control in drive-by-wire engine systems.

I am on my 3rd one of these vehicles and I just plain don't like them. Throttle response is just not right. An automatic will mask most of the symptoms, but a stick will make you crazy. I'm threatening to trade my Colorado just because the engine responds weirdly and surges. Dealer can't find any problem.

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