scheduled an apt with lexus service center. Will see how lucky we will be tomorrow in replicating the issue. I am tempted to drive a potential route for tomorrow to see if it has enough straights to help us with reproducibility.

 

Appointment was a disappointment because somehow they scheduled it for me, but did not schedule it in their system.
However, I have been driving up and down my local stretch of highway for 3 days, and only day 1 was successful in reproducing the issue. Yesterday and today's drives did not yield the results. I changed tire pressure, so it does not look like it is what was precipitating the issue. Looks like amb temperature might be one of the contributing factors though.. day 1 was hotter (95F-ish) while days 2 and 3 were 75-80F.

An advisor told me he never heard of the steering issue despite working more than a decade at this Lexus Service Center. I asked him if my current complaint is gonna be recorded in any way and he said "no". It is hilarious when people do not hear themselves speak...

I was like - well, there ya go - if you dont record this complaint and the issue is hard to reproduce, how would you get it to pop-up in the lexus system?

 

Don’t think so. My IS is my winter car, and I’ve experienced the glitch at various temperatures.
The only commonality between instances is long straight stretches at highway speeds (70+ mph).
Sounds like dealers just don’t want to be bothered by the issue. (Sending someone out to drive an hour or two with a low probability of hitting the issue, just doesn’t fit their diagnostic model.)

 

That is lame. It doesn't sound too different from my experience with Hennessy Lexus here in GA. I basically had to tell them "Look, I am insisting there is an issue." They said to bring it back if it comes up again, and it'll be in the system that I have repeatedly complained. In the system, though...

Thankfully, for me it's also very inconsistent and rarely happens.

 

Ideally if there was a ODSB logger that could read data from the steering module and log it. Things like total torque or "effort" required to move the steering and some additional parameters like steering wheel angle, rpm and speed + throttle position. They already have it there anyway, which is how the EPS works in the first place... but this is prolly too much to ask.

 

yeah, I admit it I did not have much confidence in that hypothesis. I remember the issue popping up in 2019 in april - 70-80F. I dont recall it happening during winter time though. Temp could be just irrelevant to the issue though.
I am trying to keep this thread alive just to see how far we can push this unofficial investigation.

 

With my 2016 IS, I had the issue happen in winter, when driving down to Texas. It was warmer there than in Missouri, but still not "warm" warm, like 60 degrees or so that day.

 

Of course when I went for a drive today at 11pm, (amb t around 78F) I was able to reproduce the issue somewhat. Had to drop tire pressure to 35psi cold. So, maybe lower tire pressure causes it, after all?
Also, unlike in the previous runs, my fuel tank was full. Doubt it changed anything, but who knows...

 

Again, don’t know about that. After driving an hour at 70+, my tires would be warm and in the 38-40psi range.

 

yes. my cold tire pressure was around 35.5 before the testing.. It usually hits +2psi when "operating temperature" for the tires sets in (after about 10-15 mins of driving). Incidentally, when I was testing it at 40psi, it did not wanna do "bind", so it looks like lower tire pressure might have helped there.

 

Well, with the higher pressure, your rolling resistance is a bit lower. So, perhaps that made it easier to move the wheel or reduced the forces acting on whatever is getting bound.

 

yes, but also - contact patch will be slightly bigger with lower pressure.
So, maybe it is forward pushing force that is causing it to bind, along with the steering wheel being slightly off center? I also noticed that it might be getting worse on throttle vs when it is steady or decelerating.

You mentioned that the left sweeping bends might be exacerbating the problem. I noticed that, except for me it was any turn(both left and right) where the steering wheel needs to be off center by 1-2 inches, is what causes/reveals it for me.

Current hypothesis:
force of forward thrust at higher speeds (needed to counteract significant air resistance at higher speeds) in conjunction with higher rolling resistance of tires and/or higher grip cause mechanical binding in the steering rack.

How doesn't this manifest in the initial stages of much bigger acceleration (say, 0-60) can be explained that it needs long enough time and the steering wheel micro-corrections need to be happening during that time to get to that condition. Driving on almost straight or slightly curving highway stretches accommodates that better, unlike 0-60 acceleration runs.

 

Anyone have any luck with getting this fixed? Car is out of warranty and I’d rather not pay Lexus $200 to find nothing

 

Apparently it can be fixed by replacing the steering rack. I am not sure tho, since Lexus does not have a recall on that part, and will still use the same part to fix that which is supposedly defective.

 

I still experience it on my 2021 from time to time. Notably, now that it is colder, it seems more noticeable at lower speeds, even as low as 40 MPH. It comes and goes, though.