BMW 335i Unintended Acceleration?

Originally Posted by Beenthere

My belief is that people should learn how to drive properly and not receive a driver's license until they can demonstrate the ability to drive safely under all driving conditions. Anyone who actually believes that all cars are unsafe should not drive or ride in one. It should be obvious that none of the black boxes - the ETC, ECM , DBW etc. caused this accident. It was the driver kicking the floor mat under the accelerator pedal that caused the accident. Should we ban floor mats in cars or teach people how to drive properly?

All machinery can be considered dangerous in the hands of unskilled operators. People need to accept personal responsibility for their actions and not try to blame others for their mistakes.

This is so true. JMHO but the advent of the automatic transmission took the 'learn' out of learning to drive. Every day I get behind the wheel, I am so thankful that my driver education instructor was my father; who, rally raced Porsches as a hobby. He taught me not only defensive driving, but how to handle a vehicle in an emergency; and use the vehicle to your advantage in the emergency. I see so many drivers on the roads which can scarcely pass the vision test, let alone truly know how to handle their vehicles, yet these are the same folks that are busy chatting on their cell phones or goodness knows what else while "driving". Other than just the plain joy of driving, my decision to own a MT vehicle is overwhelmingly driven by the ability to better control the vehicle with the MT. I might tear up a transmission forcibly shifting the car from a forward gear to neutral, but at least I might live to pay the bill for the tranny rebuild. (Now stepping down)

Originally Posted by DSXMachina

Hi wit, I think this discussion has been fairly civil. A lot of people have made their points and done so as best we can on a bulletin board. Sure, we invest a little emotion in our postings but overall this thread has kept to the point. None of us have all the facts, yet most of us learn a little as we go along. The points you made were well thought out whether we agree or not.
If you want to see real vitriol you can always take a peek at some of the PoliSci postings in Off Topic.

Thanks for your kind words. I just registered to Bimmerfest, and I expected friendly discussions on the car we all love to drive. I am concerned that we are going too far off. In another thread, for example, the accident victims were even called idiots, and some derogatory remarks were made as I quoted in my last posting. I am a careful driver, and I don't think I could do better than the CHP officer in the similar situation like the Lexus runaway. He steered away from more deadly crashes. We need to discuss to understand more about the car we are driving and how to deal with the inevitable. Our discussions shouldn't blame others or car manufacturers. My apologies if I offended anyone by my postings. Thanks again.

Originally Posted by DSXMachina

An automotive DBW system does NOT receive commands from the ECU (main engine management computer, also called the CPU and ECM and PCM). The throttle servo gets its command from the driver's foot and reacts to it and tells the ECU what it is doing. The main computer can only override that command/control system and shut it down. It cannot speed it up.

I don't think this is entirely true. It doesn't consider the use case for cruise control. When cruise control is turned on, somewhere buried in all that software is code that controls the throttle servo, independent of the driver's foot. By pressing either the "Accel" button or the "Resume" button, it's possible for the ECU to open the throttle and for the car to accelerate independent of the gas pedal. Therefore, it's entirely possible that an obscure bug exists somewhere that can cause an unintended acceleration scenario.

The LA Times just posted a new article regarding Toyota and unintended acceleration. How about this quote:

In a written statement, the NHTSA said its records show that a total of 15 people died in crashes related to possible sudden acceleration in Toyota vehicles from the 2002 model year and newer, compared with 11 such deaths in vehicles made by all other automakers.

Or this:

Dr. David. W. Smith, an emergency room physician from San Dimas, has yet to receive a satisfactory answer from Toyota about his Lexus GS 300. Smith said he was driving with his cruise control in Central California on Highway 99 last year, not touching the accelerator, when suddenly the vehicle accelerated to 100 mph.

The brakes did not release the cruise control or slow down the vehicle, Smith recalled. Finally, he shifted into neutral and shut off the engine. "I am sure it is the cruise control," he said. "I haven't used it since."

Runaway Toyota cases ignored

Perhaps there are some math whizzes at Toyota who have gone over "The Formula" recently:

Originally Posted by AK

I don't think this is entirely true. It doesn't consider the use case for cruise control. When cruise control is turned on, somewhere buried in all that software is code that controls the throttle servo, independent of the driver's foot. By pressing either the "Accel" button or the "Resume" button, it's possible for the ECU to open the throttle and for the car to accelerate independent of the gas pedal. Therefore, it's entirely possible that an obscure bug exists somewhere that can cause an unintended acceleration scenario.
snip

I will check the command loop for Cruise Control and see how it interacts with the other systems. I do know for a fact that on every cc system in use today, cruise is shut down when the brake pedal is touched. As for the good doctor's car "suddenly going 100mph", who is he kidding? Was he sleeping at the time? How does even a BMW doing 65 suddenly do 100 without anyone noticing?
Am I the only one who is old enough to remember when the Audi 5000 was accelerating uncontrollably and hundreds of people were coming out of the woodwork to prove it was? Even TV shows were demonstrating how it happened by faking incidents.
The problem was that it was 100% driver error. Dozens of people were killed by runaway cars which suddenly, for no reason whatsoever, lept ahead and ran over the innocents. BTW, this is why we have shift interlocks today. The sad fact is that driver error almost put Audi out of business in the US.
Now we are going to hear about hundreds of cases of runaway acceleration being blamed on drive-by-wire and other sophisticated systems. We'll see if a single independent and objective lab can show reproduceable real world evidence that this is fact. Don't hold your breath.
Edit- What about all the people with no sense of personal responsiblity who wish to blame every bad thing in their life on someone else? "Runaway acceleration" is an oh so convenient way to pass the blame and maybe end up with a little cash on the side. Watch for the ads in a newspaper near you soon; "Been a victim of runaway acceleration? Call the law firm of XYZ and get the money which is rightfully yours!"

Originally Posted by DSXMachina

As for the good doctor's car "suddenly going 100mph", who is he kidding? Was he sleeping at the time? How does even a BMW doing 65 suddenly do 100 without anyone noticing?

If the code the ECU is running suddenly goes off in to the weeds it's entirely possible for the good doctor's car to accelerate to 100mph without his authorization.

The fact that there are more of these types of incidents reported for Toyota/Lexus vehicles than of all other vehicle manufacturers *combined* is indicative of a problem with Toyotas. It's not reasonable to assume that Toyota/Lexus owners are less competent drivers than those of other vehicles. I'm a firm believer in that "if there's smoke, there's fire".

Originally Posted by AK

If the code the ECU is running suddenly goes off in to the weeds it's entirely possible for the good doctor's car to accelerate to 100mph without his authorization.

The fact that there are more of these types of incidents reported for Toyota/Lexus vehicles than of all other vehicle manufacturers *combined* is indicative of a problem with Toyotas. It's not reasonable to assume that Toyota/Lexus owners are less competent drivers than those of other vehicles. I'm a firm believer in that "if there's smoke, there's fire".

Right. ECU is in charge - not driver. Drivers may only take emergency measures. Hope the electronic throttle will soon be fail-safe.

Originally Posted by AK

I'm a firm believer in that "if there's smoke, there's fire".

So, uh, you believe in UFOs?

wouldnt you car have cut off power before u hit the guard rail

Originally Posted by Ambartsumian

wouldnt you car have cut off power before u hit the guard rail

The rear wheels were still spinning since the car stopped after its belly was landed. I turned off the car. It happened so suddenly, and I only remember that I held on to the wheel for the unavoidable crash. That fraction of a second was indeed the scary moment I cannot forget.

Originally Posted by wit3356

Right. ECU is in charge - not driver. Drivers may only take emergency measures. Hope the electronic throttle will soon be fail-safe.

It is.

Maybe OP's shoe is too wide?

Originally Posted by peripherique

Maybe OP's shoe is too wide?

Maybe, but I have a habit of driving with my shoes off. I wear tight SAS shoes for comfort.

Originally Posted by wit3356

I wear tight ASS shoes for comfort.

Fixed it for you.

Hi all,

I know this kind is a minor opinion in this forum, and don't intend to go on further.

Lastly, I copied the following from comments to the ABC news on the runaway Toyota. In all accidents, unskilled drivers are to blame, but machine malfunctions are not less. Over 6 Million crashes every year. Let's not mention crazy, drunken, or intoxicated drivers. They do exist. However, I don't believe drivers accelerate suddenly. Occasional panic stops are common to absent-minded or distracted drivers. Novice drivers may make some jerky and unpredictable moves. But skilled or unskilled, drivers rarely floor the gas. We need to properly account the machine failures even experienced drivers can not get away from. This is not to blame BMW. I highly rate German auto makers, and I own theirs. I feel safe to drive with other skilled or unskilled drivers on the road. I only feel scary to drive fallible machines.

Dave Hall | 9/11/09
I purchased a Rav 4 turbo diesel in 2007. I had only had it 6 weeks when, whilst my wife was driving it, she said suddenly took off. We live in South Africa and it was late at night and you do not just stop anywhere. She managed to control the speed below 160km/h in 60km/h area, travelling with her foot on the brake for about 5 kilometres until it was safe to stop. She then applied full brake bringing the car to a stop in a cloud of smoke as the clutch was busy burning up. In her panic she had forgotten to engage the clutch which if she had might have blown the engine. Toyota replaced the clutch free of charge but claimed driver abuse or carpet sticking on the accelerator. This enfuriated my wife and myself as my wife is not an incompetent nor unware driver and and at no stage during the 5 km dash did she feel that the carpet caused the problem. In any event she said her feet were so busy on the pedals all this time, surely the carpet would have become dislodged, the return spring on the accelerator pedal is quite strong. I felt that Toyota must have been aware of this problem as they very quickly came up with the seemingly standard response of the floor mats sticking. I am an Electric Engineer and understand computers and My first theory was a computor glitch. This happens all the time with micro processors and the solution is to switch off the power and switch it back on again. The glitch has now disappeared making it almost impossible to analyse. This I suspect is what is happening with the Toyota car processors. If they keep on thinking that the carpets are at fault, people are going to continue to be hurt.

..it's called a working HPFP

Originally Posted by slant83

..it's called a working HPFP

Originally Posted by Beenthere

If you keep believing that the real problem is the electronics instead of negligent drivers, people will continue to be injured and killed. Modern cars with electronics store fault codes to confirm when an implausible condition has occured.

They detect and store current faults, but not intermittent faults. They didn't leave a trace of Check Engine faults at start in my 335i. It must have detected faults when starting and set the Check Engine, but it was reset and the car started ok for repeated trials. If the starting problem persisted, they should have shown it. Since it occurs randomly, no record is left. It was not due to my negligent driving skill. As in airplanes, the black box installation should be mandatory in cars to leave a record of all info including pedal movements. I do believe the Toyota case is not about the floor mat as Toyota hopes for but the faulty system. It is not just the Toyota's problem though. This controversy continues since there is no evidence to replicate.

Originally Posted by slant83

..it's called a working HPFP

Great post!!! LOL

Originally Posted by wit3356

They detect and store current faults, but not intermittent faults. They didn't leave a trace of Check Engine faults at start in my 335i. It must have detected faults when starting and set the Check Engine, but it was reset and the car started ok for repeated trials. If the starting problem persisted, they should have shown it. Since it occurs randomly, no record is left. It was not due to my negligent driving skill. As in airplanes, the black box installation should be mandatory in cars to leave a record of all info including pedal movements. I do believe the Toyota case is not about the floor mat as Toyota hopes for but the faulty system. It is not just the Toyota's problem though. This controversy continues since there is no evidence to replicate.

Hi wit. When a car with Electronic Throttle Control (ETC) is started the ECU runs a lot of system tests within seconds. I don't mean to oversimplify, but what happens is too complex to go into in great detail. The ECU checks various circuits by sending a pulse down the line and checking the response. If the response is not as expected (Implausible) it disables the functions which depend on that circuit.
As an example, it checks TWO independent brake light switch circuits, and if they BOTH are not as specified the Cruise Control will not engage. It also checks other circuits before enabling Cruise but I want to keep it simple.
As for ETC, the number of checks and cross checks and check frequencies are staggering. If something-anything-is out of spec the ETC will shut down and the system will go into Limp Home with greatly reduced power (or even STOP the engine after a very short while).
All the various components are located on an electrical circuit called a CAN bus (Controller Area Network). This bus carries encoded signals constantly among the various components and the ECU. Critical signals like the floor accelerator position are done with SEPARATE devices using OPPOSITE signals. An implausible system =Limp Home.
The Throttle is similarly set up and constantly reports coded signals to the ECU. Implausible signals= Limp Home. The failsafe mode on the throttle is closed throttle.
In short, unless you can point to a fault, you shouldn't conclude there is one. Please research "Audi 5000 Runaway Acceleration" and the mass hysteria which ensued before jumping to conclusions.

DSX - there are just some itches you cannot scratch!

Originally Posted by Beenthere

Not true. Car systems store numerous implausible events, i.e. fault codes. Just because your check engine light goes off does not mean the code is erased. Some systems erase the codes after a specified number of re-starts, i.e 30 re-starts or a specified time, i.e. 30 days if no further occurance of said fault code re-occurs. If your vehicle is checked within a resonable time after a fault code is generated, it is still present until deleted by a technician.

True. But what I mean by fault is the case when the car sets the implausible events by itself, and doesn't know that it did. What you mean is the normal operation when the car detected faults. For example, if you don't close the gas tank tightly, the Check Engine light will be on. Even though you fix it and unless the computer is reset, the light will stay on for two to three weeks in some cars but will be reset eventually after 30 or 50 restarts. How long it will be on depends on cars. My case is the light went off when tried again. I mean the light was on when the car didn't start, and off if started. No record.

Originally Posted by wit3356

But what I mean by fault is the case when the car sets the implausible events by itself, and doesn't know that it did.

There is no 'car' from this perspective. There are multiple independent subsystems with built-in-test and self-monitoring functions.

It's clear you've experienced an event which was disturbing to you; and you're looking for an explanation - but it's not reasonable to argue these points as if an expert without actually educating yourself.

The cop wasn't amused when I told him that.

Originally Posted by Beenthere

You might want to go to SAE.org and see if you can find a technical paper on the strategies used on current production ECMs. I think you'll be surprised at the comprehensive system checks and validation processes used to detect faults and record them.

I agree with you on that ECM or ETC is significantly better than old mechanical throttle systems. The current cars are also very fool-proof, and reliable. However, it is true only under the normal operating condition. If electronics fail, they fail miserably. So it would be better to open up a remote chance of failures.

Now the stage is set up with many extras filing legal suits, lawyers, or even divided internet warriors adding fuels to fire. Most car manufacturers know it, but have to deny it. Admitting the fact first is a death blow to them. The story seems to evolve so that Toyota may ride first a roller coater with no loop back. 2000 complaints are not negligible, and cannot be from all drivers' errors. In fact, it would be a life/death problem for any car manufacturer to admit it first. So both car manufacturers and the agency are busy in covering-up.

Electronics are fallible. Toyota is a well respected brand for their reliable cars. The problem is partly due to the consumers' unending appetite for cool electronic gadgets compounded by the incompetence of the agency that failed to rectify the issue. Hope this will lead to the development of more reliable cars in the future. What I mean by "reliable" is the level that it is unlikely for most of us to experience any deadly car faults in our life. I feel sorry, but it is time for Toyota to show the humor of our late President Reagan had - "I forgot to dodge (the bullet)."

Happy driving.

Originally Posted by wit3356

I agree with you on that ECM or ETC is significantly better than old mechanical throttle systems. The current cars are also very fool-proof, and reliable. However, it is true only under the normal operating condition. If electronics fail, they fail miserably. So it would be better to open up a remote chance of failures.

But not totally, as this thread is destined to prove.

I would also take the time to look up 'reliability' and apply that definition to your third sentence.

To be honest, I am more disappointed in myself for following this drivel than you for propagating it.