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Toyotas Suddenly Accelerate; Owners Up In Arms

cyclocommuter writes "Some Toyota owners are up in arms as they suspect that accidents have been caused by some kind of glitch in the electronic computer system used in Toyotas that controls the throttle. Refusing to accept the explanation of Toyota and the federal government (it involves the driver's-side floor mat), hundreds of Toyota owners are in rebellion after a series of accidents caused by what they call 'runaway cars.' Four people have died." The article notes: "The National Highway Traffic Safety Administration has done six separate investigations of such acceleration surges in Toyotas since 2003 and found no defect in Toyota's electronics."

24 of 1,146 comments (clear)

  1. PEBAAC by jaavaaguru · · Score: 5, Funny

    Problem exists between accelerator and chair?

    1. Re:PEBAAC by wing03 · · Score: 5, Insightful

      I'd think not. It's called "drive by wire" technology. I bought an '09 Civic and the thing has a sensor attached to the gas pedal instead of the traditional wire directly to a butterfly valve. I read somewhere that if the PCM didn't think things were right, there's a failsafe "limp home" mode that trips the throttle plate to some slightly higher than idle position and disconnects the pedal and any other controls. One of the sales guys who I met in the process of buying this car insisted that the computer controlled throttle makes it more responsive and safer. Throttle by wire IMO, is fucking with the KISS rule.

    2. Re:PEBAAC by pandaman9000 · · Score: 5, Informative

      Throttle by wire has been proven to be extremely responsive. More importantly, it is part of a closed-loop operation, whereby the ECU can properly evaluate requested levels versus actual in pretty much everything. If the fuel line is pinched, for example, flooring it would cause devastating detonation, EXCEPT in "by wire". Once the fuel present was mismatched to the air, the ECU would force the throttle to close somewhat, regardless of pedal position. The exception is in many cases of a wide open throttle request, when some output levels like fuel overrich are ignored, and the ECU uses an internal map of what "should be going in and out, given the max power request.

      It is exceedingly easy to test the Throttle Positioning Sensor in modern vehicles. In fact, your ECU probably tests idle throttle position every time you turn the key on for a while without staring the engine. The ECU will also log 'implausible signal' for TPS that get an out of range reading, or inconsistent reading throughout the range.

      Note: This information was gathered while researching diagnosing my personal car, a B5 Audi S4. It is a summary, not the automotive gospel.

      This sounds like people getting paid for being stupid. I do not approve, but who am I, eh?

    3. Re:PEBAAC by bongey · · Score: 5, Insightful

      Throttle by wire IMO, is fucking with the KISS rule.

      To propose that somehow mechanical cables are safer because they are simpler is severely flawed.
      Have you every seen how easy it is to get a mechanical throttle to get stuck? Also in a wreck the cable the throttle can become pinched, stuck at full throttle not fun. Look at the back of street/strip drag car they have emergency kill switch on the back bumper for this reason, along with wanting to kill the fuel pump.
      A mechanical throttle lacks any safety controls. A simple cable is in fact simple, but it is a stupid cable.
      Twice I have seen a mechanical fail.
      90s Camaro SS , guy had dropped about 10k in the motor only to have the throttle get stuck, redline, broken valves.
      My Saturn has become stuck more than once when it is cold, never caused an accident.

      Just because you drive car,bought a car, doesn't give you divine insight on how a car works, and somehow your experience brings insight to the conversation.Spend a little time working on/ modifying a car and you will quickly discover; mechanical cables suck ass to put in and are more prone to failure!

    4. Re:PEBAAC by Jarjarthejedi · · Score: 5, Insightful

      "Mechanical and hydraulic systems are much better understood."

      Computer aren't exactly a new-fangled technology, and most cars built after the 70's or so have had some form of by-wire throttle control (I'm speaking, of course, of electronically controlled anti-lock brake systems which, while not fully by-wire, include a by-wire system alongside the mechanical one). I always find it amazing how people can talk about computer controlled systems are not being 'not well understood' in this day and age. Not well programmed, perhaps (though the analog there would be poorly fabricated parts, a problem that was dealt with much as poorly coded systems are being dealt with now-a-days), but not well understood? Really?

      This isn't a new technology, it's been around for a while in one form or another. Sure it's less mature than conventional hydraulic, but hydraulic are much less mature than banging two sticks together, doesn't make the sticks better than hydraulic. I think my signature sums it up quite nicely, just because drive-by-wire is something relatively new (50yrs of use) and hydraulic something relatively old doesn't make one better or worse than the other, that depends on how they function. If you want to compare the two systems that way be my guest, but just stating that drive-by-wire is worse because it's newer is hogwash.

      --
      There are two kinds of fool One says 'This is old therefore good' Another says 'This is new therefore better'- Dean Ing
    5. Re:PEBAAC by __david__ · · Score: 5, Interesting

      It is exceedingly easy to test the Throttle Positioning Sensor in modern vehicles. In fact, your ECU probably tests idle throttle position every time you turn the key on for a while without staring the engine. The ECU will also log 'implausible signal' for TPS that get an out of range reading, or inconsistent reading throughout the range.

      You are basically correct. I have first hand hacking experience with the drive by wire throttle because my Grand Challenge team automated a Toyota Prius for the last Grand Challenge. There are 2 completely independent signals that go from 2 independent sensors on the pedal to the computer throttle component. The signals have to move in lock step with each other or the computer will detect a fault. If a fault is detected the throttle goes completely off and the car has to be turned off and turned back on to recover.

      So for the throttle to stick down both pedal sensors have to fail in the same way at the same time, which seems highly unlikely to me. Or there could be a bug in the computer control section, bus as a software engineer I can assure you that that would be impossible. ;-)

  2. Put the damn thing in neutral! by the_humeister · · Score: 5, Insightful

    I have to say that the decline in manual transmission driving has really diminished people's driving abilities. It's one thing that the there's an acceleration issue. It's another thing to not consider putting the car in neutral when something like this is encountered.

    1. Re:Put the damn thing in neutral! by Anonymous Coward · · Score: 5, Insightful

      The case the media is portraying constantly had enough time to call 911 and ask for help.

      Neither driver nor emergency responder thought of this solution that really should be second nature if you've had THAT much time to react.

      Now, other cases may have been less lucky but for that specific case its kinda darwinistic.

    2. Re:Put the damn thing in neutral! by maharb · · Score: 5, Insightful

      Those that drive manuals would be more clear headed because driving is an active activity where one is engaged with the machine. I don't mean to be a dick but people who drive manuals inherently understand how the fuck a car works because it is required to get the thing moving and stopped. The new generations of people who drive only automatics truly don't understand what is going on with their cars even if they had time to think clearly and then you have the people who may know but have never had to react in that way.

      When you drive a manual transmission daily you will probably encounter several situations a year where "both pedals in" is required to keep you safe. Essentially anyone who has driven manual has practiced the solution to this problem. Anyone in a automatic has not. In a automatic cars you can just hit the breaks and forget about what that meant the car had to do.

      So I believe the parent is correct in his assumption that manual transmissions create drivers that are better equipped to handle situations on the road than the average automatic only driver. I am not saying that every person who drives a manual is a great driver, just that they are better equipped to handle situations on the road assuming all other variables are equal.

    3. Re:Put the damn thing in neutral! by cyn1c77 · · Score: 5, Insightful

      because everyone is always so clear headed when their vehicle suddenly accelerates for no clear reason,and\or has the time to calm down before they collide with something.

      Way to prove the grandparent's point!

      Seriously, if my car were to accelerate without warning, the first thing I would do would be to push down the clutch. The second would be to apply the brake. And if that didn't work, I would pull the emergency brake. Meanwhile, aim for something soft without people in it.

      If you can't mentally run through that four step list in a throttle malfunction, you shouldn't be driving. I mean, come on...The first two actions should be instinctual, panic or not.

    4. Re:Put the damn thing in neutral! by icannotthinkofaname · · Score: 5, Funny

      Did you just make a computer analogy for a car discussion?

      This thread is so backwards....

      --
      Let q be a radix > 1. I am in ur base-q, killing 10 d00ds.
  3. Same thing happend to Audi a few years ago by scotts13 · · Score: 5, Insightful

    And again, nothing was ever found to be wrong with the cars. Seems most of the drivers were used to American cars, and the Audi had both brake and accelerator a little to the right of the more typical position. They were pressing the accelerator instead of the brake. Fact is, in almost all commonly available cars, if you stand on the brake and on the accelerator simultaneously, the car will go nowhere. For events to have happened as described, you'd need the simultaneous failure of two unrelated systems, which both healed themselves miraculously after the event. Additionally, same as last time, there are a few unfortunate cases followed by a deluge of similar claims. I wonder why...

  4. I have seen this... by theendlessnow · · Score: 5, Funny

    My Geo Metro had the EXACT same problem. It would suddenly jump from 1mph to 1.1mph very quickly. They wouldn't admit the problem either. We figured it was due to having an odd number of cylinders.

  5. Re:Floor mat, really? by SteveWoz · · Score: 5, Interesting

    I have owned many Prius's. I currently drive a 2010 one. Let's say that I'm in some place where the speed 85 mph is legal. I can nudge my cruise control speed lever and my speed barely goes up, say from 80 to 81.I nudge at again and again, up to 83. Then I nudge it again and the car takes off, no speed limit. Nudging the cruise speed control lever down has no effect until I've done it about 10 times or more. By then my Prius is doing 97. It's scary because it's so wrong and so out of your normal control. I tested this over and over the night I observed it.

    It's scary because you don't think of things like putting the car in neutral when this happens. I am sure you can't turn the car off with the keyless power button, the only option on this model.

    Braking does disable this scary cruise control effect. It is a natural response, so the problem is mitigated a great deal.

    I have not seen this happen before so I think it's new to the 2010. I have the package which includes parallel parking assist and cruise control distance limiter.

    --
    OK a new size TV
  6. First Hand Experience by hubang · · Score: 5, Interesting

    Toyota has a serious problem. Have for years. It's not the floor mats.

    I was driving a '98 Toyota Camry. Foot on the brake. B-R-A-K-E. Yes, I know the difference. Car in drive. Waiting for a right turn. The car revved up high. I did manage to throw it into neutral, and the engine continued to surge. Luckily I didn't hit anything. And it was pure luck.

    The car did not have All-weather floor mats.

    I have racing experience, and a background in Mechanical Engineering.

    The reason the problem hasn't been found is that it's probably a subtle fault (like the AT&T crash back in the early '90s, or the stress concentrations in the DeHavilland Comet) and they're (by they I mean the NHTSA) probably not looking very thoroughly, due to lack of manpower. They don't do investigations of car crashes the way they do for other serious engineering failures, like plane crashes or bridge collapses.

  7. Throttle Position Sensor by Anonymous Coward · · Score: 5, Insightful

    I had this same problem with a 1989 Jeep Cherokee in 2000. People died because of similar problems. On the internet and in court, Jeep claimed it was user error. The problem is people don't know enough about their cars to diagnose it, but it turned out to be the Throttle Position Sensor. Which would randomly rev the engine to 4000 RPM's instead of the idle of ~900 when you put it into gear. Yes, absolutely unpredictably. It was not easily duplicated for a mechanic, because when the TPS first started to go bad, it was very infrequent.

    The problem is your normal routine is start the car and put it into gear almost immediately. The engine takes more time to rev noticeably past idle speed, at which time you're already moving and lost control of the car. Jeep claimed this was an unreasonable explanation, because they had an engineer sit in the car, depress the brake, put the car into gear, and then rev the engine and be unable to overpower the brakes. I found this only to be true if I were standing on the brakes, something I wasn't in practice to do, from a stop. It also overlooked the problem that once you let the car start moving, getting it stopped again was extremely difficult.

    So everyone always assumes there are enough idiots out there for it to be driver error, but it happened to me, so I never trust any of the car manufacturers when this problem creeps up which it does fairly often. Also, it seems like extremely poor engineering on the manufacturer's part to fail to acknowledge this possible avenue of failure. Seems more like they are just covering their asses to avoid culpability.

    I was in college at the time, and this is probably one of the more valuable lessons I've ever learned in engineering and something I think would be valuable in software engineering also. Never, ever dismiss complaining customers as morons just because its the simplest explanation especially regarding a safety issue. People actually put up with a lot. More often than not, when people complain and it is difficult to do so, there is merit to the complaint. A proper investigation is required, and a open mind, and wide imagination help determine the failure states.

  8. Re:Carmakers lie by mister_playboy · · Score: 5, Interesting

    This is a "feature" of German cars due to a law in Germany mandating that the speedometer must NEVER read lower than real speed... even if the car has non-standard wheels and tires fitted.

    Porsche and BMW exaggerate speed the most, and the theory is because owners of these cars are quite likely to upsize their rolling stock (and thus make the speedo read lower). It's annoying, but it's simply in response to a legal requirement.

    Car and Driver did a test on several vehicles a bit over a year ago. GM vehicles were the most accurate... around +1 mph on average.

    --
    Do what thou wilt shall be the whole of the Law ::: Love is the law, love under will
  9. Re:Floor mat, really? by Divebus · · Score: 5, Interesting

    I used to have one of those "sudden acceleration" Audi 5000's (1979). It happened to me once and I figured out exactly what happened within five minutes. It wasn't the computer or the floor mat or anything. The accelerator pedal linkage was a solid rod which ran up a few inches from the tip of the pedal, then turned left to pass behind and above the brake pedal. If you put the arch of your foot on the brake pedal, your toes could contact the accelerator rod and depress it. Even light braking action was enough to impart enormous acceleration. The harder you stomped on the brake, the more the engine overcame the braking action. The fix was to put a metal guard plate over the rod behind the brake pedal.

    --

    Most of the stuff on /. won't survive first contact with facts.
  10. Re:Carmakers lie by nlawalker · · Score: 5, Informative

    How do you think the speedometer that the odometer is connected to works?

    Besides, wheel radius on a car is variable and is constantly changing. This is one of the primary reasons that speedometers read fast - the car maker provides a conservative buffer to ensure that no matter what your tire wear, air pressure and wheel size are, there is a much better chance of you traveling equal to or slower than the displayed speed, as opposed to faster than the displayed speed.

  11. OMG - I own a Nissan Sentra and it happened to me. by crispytwo · · Score: 5, Informative

    The government & Toyota are probably right about the floor mat. But that's what recalls are for.

    This is exactly what happened to me and I was heading to a cliff - 3rd gear - floored and I had the presence of mind to turn off the ignition. Seriously - I was terrified.

    Picture this, you turn a corner, accelerate, change gears, and suddenly you are going around 80 Km/h with about 1 block to the edge of cliff and a 90 degree turn on a residential street with a cliff in front of you.

    I had the time to turn off the ignition and jerk to a stop... BTW taking it out of gear under full acceleration is not simple either. I can hear the vacuum cleaner sound of the engine too - it was crazy. However, when the engine red-lines - it kill the accelerator for a second and then lets it restart... grabbing the ****ing anything with that is un-fun.

    AFTER it stopped I could diagnose the problem being that the driver's side floor mat came off the hook that is supposed to hold it in place and inched up over the gas-pedal... thus couldn't un-press it until the carpet was pulled back.

    Since there was a slot in the peg that holds the carpet in place, I took a handy dandy twist tie and wrapped the peg with the carpet in place preventing the carpet from EVER popping off that peg. Since then - no scary shit.

    Toyota and Nissan should fix this problem - at their cost - and it should be a recall. - After all - it's a 10 cent fix - a peg that has a simple spring latch on top would fix it with no problems. Picture hanger anchors have used that technique for decades now.

  12. Re:problems with complexity by tokul · · Score: 5, Insightful

    F-22 raptor - 1.7 million lines of code F-35 joint strike fighter - 5.7 million Boeing 787 - 6.5 million Premium class automobile - ~ 100 million

    F-22, F-35, Boeing - flown by professionals
    Premium class auto driven by morons

    Two different things. Different environments and different safety measures

  13. Re:Reproducible testcase by SvnLyrBrto · · Score: 5, Funny

    Look who you're replying to. He's probably fixed it himself by now. In fact, he's probably re-wired and re-programed the whole thing to get at least 25% better mileage and acceleration by now.

    --
    Imagine all the people...
  14. My sudden-acceleration Audi experience by MasterOfGoingFaster · · Score: 5, Informative

    The Audi 5000S was never defective...

    It might be true that some people hit the wrong pedal, but I actually owned an Audi 5000 Turbo and experienced sudden-acceleration.

    I was driving down an Interstate highway in Texas, when the car suddenly began accelerating. I was on cruse control, and my feet were not touching any pedals. Since I'm comfortable at high speeds (past racer) and the weather and road were good, I was pretty calm. I put my foot behind the accelerator pedal and pulled back. It moved freely. I realized the cruse control had opened the throttle wide open.

    I tapped the brakes to shut down the system. The pedal wouldn't move. I pressed hard with both feet, and could feel the arm flex, but it would not move. Realizing I had no brakes, and a wide open throttle, I hit the dash switch to shut off the cruse control. As the car slowed, the brakes slowly became operational. I noticed the turbo boost gage was now reading negative pressure. When the turbo boost was on, you could not apply the brakes.

    It turns out that there was a check valve between the intake manifold and the brake booster. If it leaks/leaks, then high pressure air prevents the application of the brakes.

    My belief is there was a bug in the cruse control, or it was susceptible to outside interference (trucker with hopped-up CB radio?) Combine that with the check valve issue and you have a car that could very well exhibit the behavior that 60 Minutes indicated. Those people said the car suddenly accelerated and the brakes didn't work. And that matches my experience exactly.

    I contacted Audi USA, but they blew me off. The dealer didn't care either.

    I'll let others argue whether this is a 'defect', but I've been cured of ever buying another Audi.

    --
    Place nail here >+
    1. Re:My sudden-acceleration Audi experience by RingDev · · Score: 5, Interesting

      Virtually all (all that I have ever worked on) gasoline cars use the vacuum created in the intake plenum to operate the brake booster. Some cars use an electric vacuum motor to maintain the power breaks in designs where there is not a consistent vacuum or not accessibility to the plenum.

      If you have a leak in your plenum or vacuum booster line, your engine should run rough and your breaks will be much harder too push.

      The system will never prevent the application of the breaks, but it does mean instead of having power breaks, you are relying on the mechanical advantage of the pedal and your own leg power to stop the car. If you go back to the 60's you'll see "Power Brakes!" as an option you could add to your car.

      Another option to shut down the cruise would be to put the car in neutral. If the engine continues to rev uncontrolled, it likely isn't the cruise control that is at fault.

      I have experienced 3 sudden acceleration incidents. 1 was in my Fiero when the 15 year old Cruise Control vacuum got stuck (turning off the CC restore normal driving) and the 2 others, in a '87 Dodge Raider and an '06 Golf TDI we both due to floor mats not being properly installed. The velcro backing on the Dodge's mats had worn out, and the dealer threw in rubber mats on top of the stock mats in the Golf. In both cases the mats had crept forward enough to interfere with the gas pedal.

      I'm not saying that there isn't a problem with any specific design, but in my personal experiences the faults have tended to center around pedal interference and/or aging mechanical devices.

      -Rick

      --
      "Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs