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Sudden Unexpected Acceleration today

Discussion in 'Model 3' started by AZM3, May 4, 2018.

  1. SageBrush

    SageBrush REJECT Fascism

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    Glad to hear, but I think I'll use chill mode routinely.
    I used to enjoy jumping off cliffs and out of airplanes but from cars I just want safety and to not harm others.
     
  2. SageBrush

    SageBrush REJECT Fascism

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    According to WK, an uncommon thing.

    I know that I am capable of lying to others, but I know I am lying. This group that WK talks about are probably lying to themselves as well.
     
  3. cab

    cab Active Member

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    Agree with this 100%. I had a Volt for 3 years and have had my Model S for almost 2 years...and I STILL did this the other day in a parking lot ...dang near careened into another car and had to swerve out of the way. I still remember the look on the face of the guy in the other car...ugh!
     
    • Like x 2
  4. xmetal

    xmetal Member

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    That is definitely a shame and glad that everyone is ok. While anecdotal, I had an instance of this years ago.

    Now, I have raced cars at an amateur level for years and was actually at an autox when this happened. I, for all my experience in driving cars fast, truly and 100% thought that I had planted my foot on the brake in a moment of "panic" when in fact I did hit the accelerator. In my mind, I absolutely believed at that moment I was on the brake and would swear to it, but the car lurched forward and in retrospect I made the mistake, put my foot in the wrong spot and accelerated.

    Our muscle memory is also very different for those pedals. The brake usually requires a firm pressure when the accelerator is much more delicate. We don't consciously differentiate but if you step on the gas the way you do on the brakes, you really end up buying the throttle.

    This happens, and the human memory is just not accurate. While there is a tiny chance your wife found the one time this happened, it is unfortunately more likely that she messed up just like I did.
     
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  5. jpaz

    jpaz Member

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    All read with interest. Maybe I'll turn "creep" on (turned it off the day I got the car). But I drove manual transmission ICEs for years so having the "creep" off is no different than depressing a clutch.

    I've had the opposite experience many times when using "auto park." As the car slowly maneuvers (actually it is kind of like having creep on), I've barely touched the brake where my foot is hovering and the automatic parking maneuver immediately stops. While it can be annoying, it is better than me accidentally pressing the accelerator (BTW, love it when you refer to that pedal as the "gas" pedal in an EV :) )
     
  6. AZM3

    AZM3 Member

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    AZRED - you and I are as much Tesla fanboys as any other on this forum. I have been a Tesla shareholders since the stock was $22. I will take your note above as a compliment to my writing style but make no mistake - this is not to arouse paranoia or induce hysteria among the members. After all, everyone on this forum is well educated and informed. It would be foolhardy to point blame on one v. the other until the facts are known. My reason to post here is to get educated on member experiences and learn something about our cars in the process.

    For me safety of my family and friends is paramount - no matter what. As I said in my earlier post, if there's a slightest chance this is not a result of a human error, then we owe ourselves to get educated on the root cause and find the circumstances that lead to such behavior. No one here on the forum can guarantee me that Tesla or any other company has worked ALL the bugs out of their firmware and there can be NO CORNER CASES that might result in the car misbehaving.

    Guess different strokes for different folks - for me it's the safety features of the car or the SUA, for others its the panel misalignment, color fading, charge loss etc. etc.
     
    • Informative x 1
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  7. AZM3

    AZM3 Member

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    [QUOTE
    This happens, and the human memory is just not accurate. While there is a tiny chance your wife found the one time this happened, it is unfortunately more likely that she messed up just like I did.[/QUOTE]

    Well put - I hope for it too. It's easy to correct a human behavior than to get to the bottom of what I am perceiving as chasing ghost. Someone earlier said - Blame it on the Aliens. Guess I will blame Anakin Skywalker for yesterday's incident.
     
  8. wk057

    wk057 Senior Tinkerer

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    I think this is an entirely different issue though. You intended to accelerate, but were in the wrong gear.

    Also, I believe at some point Tesla made the car go into neutral instead of remaining in the wrong "gear".
     
    • Informative x 1
  9. DR61

    DR61 Member

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    When I was very active in autocross competition many years ago, I noted that many top competitors used left-foot braking, even with manual gearbox cars. It is also common in other areas of motorsports. I learned to do it by practicing with auto-trans vehicles first. I used it occasionally in competition with manual gearbox cars, but now I routinely left-foot brake in all non-manual vehicles. When driving my manual vehicle I automatically switch to normal right-foot braking.

    With left-foot braking the probability of a UA error is greatly reduced. Modern auto vehicles and EV's stop or greatly restrict acceleration when the brake is engaged. Even in older vehicles the brakes are more powerful than the engine. Learning the technique takes commitment as one needs to develop left-leg muscle memory for the proper inputs to the brake pedal.

    There are many discussions of left-foot braking in competition. Here is one in reference to street driving:
    Why You Should Be Braking With Your Left Foot
     
    • Like x 2
  10. Texas

    Texas Member

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    I have the unique experience of having experienced two sudden acceleration events. My car is a May 2015 P85D-L and both events occurred within a few months when the car was about a year old.

    Both occurred in parking garages where I was maneuvering at 4-5 mph, and both occurred when suddenly and unexpectedly I hit 6 -8” high curbs located in places where I didn’t anticipate hitting anything. My knee jerk reaction was to hit the brakes, of course. Unfortunately, because “Creep” was off, my foot was on the accelerator, not above the brake. So when I “hit the brakes” I believe I actually hit the accelerator. I certainly power launched right there in the parking garages and lurched about 15-20 forward.

    Thanks to good luck, I didn’t hit anyone or do any property damage, even to the car, although I was really shaken. With two dangerous sudden acceleration events occurring under identical circumstances, I clearly needed to find out exactly why this happened.

    My first theory was that my size 12-13 feet hit both pedals. I frequently got “both pedals pressed” warnings on the dash. But I couldn’t replicate this. Then I tested whether the pedals were too close together. This theory didn’t survive either. The only remaining theory was that Creep off placed my foot on the accelerator, the wrong pedal in a knee-jerk braking response.

    I now keep Creep turned on, so that when slowly driving around in a parking garage the natural place for my foot is over the brake. I have had no more “sudden acceleration” scares since then.

    I have posted this history several times on TMC because the sudden acceleration comments keep coming up. Those whose cars were damaged usually insist the car caused the problem. Everyone else tend to say pedal error. Many posts suggest Creep off as being the root cause of many of these accidents, which my experience clearly supports.

    An interesting point of view came up recently on Quora: a valet parking attendant said he and the other valets considered Creep off to be a safety problem (although he evidently didn’t know about Creep on being an option).

    I hope someone from Tesla is reading these threads.

    I recommended that Creep off be removed as an option. Alternatively, my recommendation would be that Creep on be the default, with Creep off becoming available only after the first 500 miles and then only for profiles expressly opting for Creep off after a touchscreen notice mentioning possible sudden unintended acceleration at low speeds.

    It would also be a good thing to include “Creep on” as part of the Valet setting, since the almost uniform experience of valets is with ICE automatic transmission cars.
     
    • Informative x 7
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  11. bandido

    bandido Member

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    Lots of great information in this post and I am glad no one was seriously injured. One other weird circumstance that I have seen in my own vehicle, not true "unexpected acceleration," but surprised me acceleration. I had forgotten the cruise control was engaged and set at 2 car lengths. The car will come to a complete stop and accelerate as expected, HOWEVER, the car in front of me turned suddenly away and the car saw open space and accelerated much more than I was expecting. I quickly drilled the brakes, but if I had not, or hit wrong pedal, it would have been bad. Not sure how to engage cruise on the Model 3, but another thing to watch...
     
  12. gregd

    gregd Active Member

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    I have always driven automatics (and my EV) with two feet. I learned to drive on a manual transmission car, and have always had them as my daily driver. My wife hated (despised) manuals, so I was constantly switching back and forth between vehicle types. It seemed more natural for me to use my left foot for the brake in the automatic, since the sequence for stopping in a manual was to push the left foot in as I take the right foot out, followed by the right foot moving over to the brake. (No snippy remarks about doing the "hokey pokey", please.) In the end, the right foot still ends up on the brake, along with the left if it's an automatic; the overall movements are the same for all types of cars. As a plus, that first movement with the left foot puts me that much further along in getting the car to slow down in an automatic / EV, because the left foot is already on the brake.

    The only thing I miss with the Roadster is that the brake pedal is very narrow, compared to a typical automatic's, so it's not possible to put both feet on the brake pedal when sitting at a stop light. I usually end up resting the right shoe over the edge of the left.

    Relevant to this thread, in a surprise stop situation I've caught myself pushing the left pedal in my Roadster expecting the clutch, and instead applying the brake more suddenly than I had expected. It's only happened once or twice, and no harm done (no passengers at the time to frighten), but it showed me that "muscle memory" is quicker than conscious thought. It's probably not reasonable (or wise) to try to re-learn to drive with two feet - muscle memory is hard to change - but I recommend it for anyone who is just starting out.
     
    • Informative x 1
  13. Electroman

    Electroman Supporting Member

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    Just curious which car were you driving then?
     
  14. SageBrush

    SageBrush REJECT Fascism

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    Tangentially, this is my emerging criticism of radar assisted cruise control: it messes with my muscle memory. Instead of just moving my foot to the brake pedal I find myself screwing around with the cruise.
     
  15. AZM3

    AZM3 Member

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    There is a concerning aspect to the way TACC is engaged in the M3. When you double press the stalk for Autopilot and single press to cancel it - the TACC is still active and can definitely cause sudden acceleration to resume. I have been caught off guard sometimes with this behavior on freeways. I know you could cancel it by braking, however there should be an option to press one of the wheels to re-engage TACC just like in normal cars and the default behavior of exiting auto pilot should also exit TACC.
     
  16. mongo

    mongo Well-Known Member

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    Well we can't, since we don't have code access, but the industry has created specialized programs that test and verify code design to validate that there are no loose corner cases. Then the routines are wrapped in check calculations with shadow ECC memory and run on specially designed safety processors with dual cores in lock step. Hercules (processors) - Wikipedia
    Airliners are fully fly by wire, that's the level of fault elimination that has been achieved.

    If you are interested, the transcript from the Toyota UA case had lots of coverage of the technical aspects and where their SW failed to maintain redundancy, thus allowing for the possibility that the UA was SW induced.
     
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  17. Joe F

    Joe F Disruption is hard.

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    I’m sorry for the OP and his wife having had this problem.

    Have been driving with 2 feet for 50 plus years with automatic transmissions, and have had std trans cars and trucks as well. Fortunately I suppose, this is how I drive the Tesla, although with regen my left foot is only at the ready for times when the unexpected happens. Much faster reaction time to hit the brakes in an emergency situation IMHO.

    I can understand how in a panic moment how one can make the mistake of hitting the go fast pedal. Something to remember to drill home for new EV drivers before letting them get behind the wheel.
     
    • Informative x 1
  18. Catman20009

    Catman20009 Member

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    Sorry about the accident. Interesting discussion. I thought when I finally get my M3 the first thing I'd do is turn off creep. I'd never thought about an issue of needing to accelerate when parking without creep. All I thought about was how nice it would be at traffic lights. Good to know. Perhaps I'll keep it on. At least for a while.
     
  19. tpatana

    tpatana Member

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    My first car was running so bad, I had to learn left-foot breaking or the car would stall every time I lifted my right foot from gas :) Basically had to learn similar to heel-toe, but with my left foot using both clutch and brake :)
     
    • Informative x 1
  20. SageBrush

    SageBrush REJECT Fascism

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    This has been an interesting thread and certainly informative for me so thanks to all.
    To OP: had you collected facts first (like log information) and then posted, a lot of rancor could have been avoided.
     

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