GXAlan

Yeah, even though I am critical of the (lack of) information you have provided, this is the best place to get people brainstorming.

Let's start with the basics about suspension, tires, tire pressure, etc.

When it just starts raining, oil and grime comes up to the surface which makes it the most dangerous time. In SF, the street cleaning is pretty lousy given the number of cars.

Then the road paint is slicker than the Tarmac. So you lose traction there.

Then there are some on-ramps in SF where they put a metal grate for drainage in such a way that you run over them mid-left turn which encourages traction loss. (280S at Mariposa is one good example).

at the end of the day, your goal is to be safer whether it involves new car/car repairs or it involves modifications to your driving or environment.

Ascari_2

Does the LS have steer-by-wire steering or is there a mechanical link between the steering wheel and the tires. The obvious reason I ask is that if there is a mechanical link, your front wheels wont turn by themselves without your steering wheel also turning.

GXAlan

I believe only the Infiniti Q50 is the true full electric system.

The LS has electric boost and electric variable gear assist. there was a recall on the 2010 era setup
http://lexusenthusiast.com/2010/05/27/lexus-ls-recall-video-demonstration/

but no known problems with the newer cars...

Ascari_2

So with that in mind (and I believe someone else mentioning a three degree maximum variance which can be ascribed to the variable gear assist) a drastic turn in the opposite direction of your turn without the steering wheel turning is impossible unless your steering system broke mechanically.

From personal experience, you seem to be describing a classic case of understeer where you want the car to turn and the car just keeps going forward. There is no need for high speeds for this to occur. For all you know you could have hit a slick patch in the road. Combine that with wet conditions and a car that weighs a considerable amount and you have understeer.

roadfrog

Not sure of it's value to you, but this thread has some information which may be of interest to the OP. It relates sudden steering loss, shaking, or complete reversal of steering input. In general, it appeared that the ballasts of aftermarket HID systems were interfering with the ECU of the P/S unit/motor.

https://www.clublexus.com/forums/is-...ering-out.html

SerentyNow

Well, Nospizone, perhaps you have access to empty parking lots given that you also have a Ferrari. Here in Marin County, our parking lots tend to be full during the day and, if I were to go to an empty parking lot in the middle of the night, set up flood lights to do a video, splash soapy water on the ground to reproduce a skid, and try to have my wife record all of this, it is quite likely that the police would come and take us away in handcuffs. Could a film studio find a place they could rent to do this for several thousand dollars? Probably. But should I have to go to these lengths when there is a potential safety flaw simply to prove what Lexus should want to know already? Now there is another way, of course. A class action lawyer might very well want to do this kind of test and be willing to pay for it. So, maybe you should vote for three.

Now about the downhill roll. I have driven both manual and automatic transmission cars and, know what to expect on a steep hill with a manual transmission. But it isn't true that all automatic transmissions behave the same way. My wife's Toyota Avalon is just fine on steep hills. The problem with the LS460L is that the idle speed is very low and cannot be adjusted, according to Freeman Lexus. The computer insists on that 750 RPM speed. But, given this is computer set, and the computer probably also knows the slope of the hill the car is on, and its direction, then the solution would be to program the idle speed to 1500-2000 RPM when the car is put into reverse on a steep hill so it would maintain its position when the brake is released. If you've been to San Francisco, you know there are plenty of steep hills here and while some cars might roll forward a little when put in reverse, while facing downhill, very few would roll as freely and as fast as the 2012 LS460L and I DO have a video of this rolling situation if you would like me to post it. I sent it to Lexus too.

Now you're in Massachusetts, but if you know someplace in Marin, Sonoma, Soloano, Alameda, Contra Costa, San Francisco, or San Mateo Counties which would agree to allow the test you suggest, please tell me. Maybe they are easier to find where you live. I just don't know of any.

Ascari_2

Idle at 2000rpms?!!?! Now that's what I would call a safety flaw.

Useful link

RodT

lmao!!!!!!!!!!!!

broken_tsi

iTrader: (1)

Why not use the brake hold feature on steep hills?

roadfrog

And this is different from ANY vehicle manufactured since the 1980's HOW???? 750 rpm is the same as any other vehicle and so is the fact that it cannot be adjusted.

Ascari_2

To be fair, I have seen my ISF idle at ~500 rpms.

But I am more interested in seeing a car idle at 2000rpms! Something tells me these engines generate enough torque that you would be doing a burnout every time you come to a light

roadfrog

Yes 500-800 rpm. My point was that these are normal idle speeds and are computer driven. 750 rpm is the norm for most vehicles +/-100 rpm

SerentyNow

Let me try again. I think one of my replies is missing. Of course car companies must be selective in investigating design flaws. However, their dealers can't be expected, nor do they have the facilities to investigate all design flaws. Now I found three, of which two are mentioned here, and I made videos of all but the skid. This should give my complaints some credibility. At least enough for Lexus to test the only one I could not video tape, especially given the safety concern, Clearly you do not want a car's traction control system to over react and cause an accident.

Also, Both Freeman Lexus of Santa Rosa and Lexus Corporate have the video of the car rolling freely down a grade of about 20%. Freeman Lexus says I do not have a faulty transmission nor can they increase the low idle speed from 750 RPM to avoid the car rolling down hill as it is computer controlled. Now what Lexus might be able to do is adjust how the computer uses it hill sensor to increase the idle when the car is put into reverse while facing downhill. But they won't.

I would video a skid test if I had a place to do it. None of the dealers I spoke to knows of one in the Bay Area and I can't sneak into a parking lot at night to do a test without being subject to arrest.

When Lexus insists all problems be duplicated by their dealers and they are only considered defects if the problem found shows the car is not behaving as designed then this rules out design flaws entirely even as a possibility. How can they even know how many people have complained about skid issues unless they keep track of them? And if Marin Lexus (who I went to first) tells me the car is performing to design and Lexus has no record of a problem, wouldn't that be what everyone is told who goes to their dealer? Only those who complain directly to Lexus, or NHTSA would have their problem recorded on a database. This is likely a small fraction of those who had the problem. If I had the email addresses of every Lexus owner I think I could prove this. Of course, Lexus does. But I don't think they're about to ask. I think they would rather not know. It's cheaper than a recall. And, of course, Toyota has done this before and paid 1.2 Billion for doing so. Who do you think Lexus learned from?

Ascari_2

What makes you the authority on what is and isn't a design flaw. The mere fact that a car performed outside of YOUR expectations does NOT make said occurrence a flaw. In addition to that you expect Lexus to do what, transport your car to their test track, get their test drivers, and start trying to replicate your description of understeer? Your description of the car turning its wheels sharply to the left (and I quote "the skid control turned the front wheels sharply to the left causing me to careen into the lane to my left") is impossible without your steering wheel turning! Now if you are saying that the steering wheel was forcefully turned while you were making the turn, then it's a different story. But as of this moment, you have failed to clarify this point. I said it before and I will say it again. What you experienced was understeer. Your front wheels lots traction and the car continued on its forward momentum creating the impression that you were no longer turning right. This is not a design flaw. This is how a normal vehicle reacts when its taken outside its limits of controlled driving.

So somehow you know for a fact that a the Lexus ECU is capable of varying its idle speed based on the incline of the car? Can you please elaborate on what makes you an expert on what Lexus can and can't do? You need to realize that your LS weights 4500+lbs with you in it. This is a lot of weight to keep stationary on a 20% incline. Automatic transmissions vary in their behavior and the roll-back that you are describing is not uncharacteristic of what other cars do. Do all cars perform this way? Obviously not. But neither do all cars remain stationary on a 20% incline.

There is not a single large parking lot where you can take the car up to the 10mph (that you claimed this happened at) during the day after some rain and make your regular right turn without being arrested?

...

sktn77a

iTrader: (2)

I don't think the rolling on steeper hills is a design flaw. Some cars will hold on a given (steep) hill and some won't. Steering problems associated with computerized stability control would be a defect but I think we have established that your car did not "self steer" into the slide. So I'm not sure what's left to discuss here?