BrotherLex

I just had this done as well. Completely fixed the issue. Also, one complaint I've had about the RX was that the steering felt too light for me. My GS feels perfect but I had to put the RX in Sport Mode to get that same feel. Much to my delight, the steering weight is much better after this SB software update. Have any of you had the same experience? I know the service advisor noted my complaint on the work order but the tech didn't indicate any other work except the TSB.

javapro

As I mentioned a couple of months ago, after applying the TSB the hesitation and droning were pretty much gone. Unfortunately, the hesitation is back. I started noticing it little by little over the last two month since the update. Now, I think it's pretty much back to where it was before the update. Anyone is noticing the same? Is this because of the transmission "learning" your driving behavior so that if you don't push it like crazy, it "thinks" that you would like it to stay in higher gears longer hence hesitation? I am a pretty fast driver but don't really floor the gas after every stop.

FastFord

Don't know if it's back to where it was, but I do think there is something going on. Last few days it's been weird, hesitates, jumps another time, no gear, all over the map.

FastFord

I know it has to do the learn thing after the TSB, but I don't know if disconnecting the battery for a while, if it has to do the learn thing again.

Funny cause it was running very well until lately.

But you have given me an idea....I think I'll go try it! Now

FastFord

To disconnect the battery.

PeeVee

I don't think that disconnecting the battery would reset things. The computer must be using Non Volatile Memory (NVRAM). It remembers even when the power goes out. Like a flash card.

I wonder if Carrista is able to reset.

FastFord

Ok so I did the battery reset. Disconnected the battery for 15 minutes. Hooked it up and started the car. The system did a re-load and said not to shut the car off. The only thing I noticed...so far, is the auto down mirrors in reverse was turned off. Pushed the button and back to normal.

I have only driven for 30 minutes and did not notice any significant difference. Maybe it was just in my head but the throttle response seemed a little more sensitive. It did not act-up as it has been, suspect more driving time is required.

Conclusion so far...no significant change. Certainly not like when the TSB was done. I will post in a few days with an update.

FastFord

I agree that it probably would not do much, if anything. I thought I would just give it a try to see if the "learn" in the transmission would be affected. Plus this was much easier than making an appointment with the Dealer, and making a trip there. I also wanted to see if it would load the TSB or default back to how it was originally. Too early to tell at this point.

JT4

Same here, years back MB must have reset the shift adaptions at least 6 times on our 2011 ML350 and each time it would shift better at first. Then anywhere between 2-5 weeks it would revert back to its weird shifting / hesitation..

I really feel for everyone here dealing with this because I know from first hand experience how frustrating this can be.

FastFord

Update on the battery reset ecu.

So I thought the car was starting to do the hesitation thing again. Did the reset and drove around today.
I can't tell if it's noticeably better, but it did not stumble at all today. Accelerator seemed to be a touch more responsive.

It was not dramatic, but I think it helped. For two minutes of work, it was worth it....even if it's in my head.

I do have the TSB installed and it has been working fine up to a few days ago.

JT4

I have never used any of those type of products so I can't say from experience. But from the reviews I have read from people that have used them, they seem to be happy with the results.. I am not too familiar with the one you posted, the one I have heard good things about is the Apexi Smart Accel Controller.

I believe someone a couple of pages back in this thread mentioned he just installed one in his GS..

s4iscool

+1, I think there was another person peddling this and Im more than skeptical...however, if a reputable tuner like APR/AWE/GIAC did a full tune on the RX350, I would buy it...they could fix this guaranteed. Which is what is maddening...Lexus CAN fix this, but for some reason, perhaps EPA issues, they cant get the fix right...look at the new people also commenting about how the problems resurface after the TSB is applied.

randomwalk

Hmm...this is disturbing. I was going to get a 2017 Lexus RX 350 but looking at this, I am having second thoughts.
I used to drive a 2008 LS460 and experienced the same exact problem...when stepping on the gas at various speeds/RPMs (and it doesn't happen all the time), the car doesn't accelerate while RPM climbs to like 5k+....let go of the gas, and step on it again then it goes.... I did the TSB ecu flash and all...the problem comes back regardless. It happens sporadically so it's extremely hard to diagnose (for the dealer) and to even show the dealer the issue. It sounds to me like the damn car has too many gears (8 gears), while driving it's great (smooth) but too many gears confused the transmission/ECU to up shift or down shift or something. Anyways, it looks like the new RX now has 8 gears...same issue???

FastFord

And it's not just Lexus that is having issues with 8+ speed trannies. I have had the TSB also and it is better, but not where it should be. I would not buy this car equipped with this transmission. A real change will have to be done, and proven.

However, I am going to get the 450H next time. Good reviews after the initial "get use to" cvt. I have driven a few but only for an hour or so.

I love how the 350 drives and even with it's temperamental transmission it's still a great car.

javapro

I went to the dealer for my 20K service a couple of days ago. I mentioned that I still had issues with the tranny hesitating but they said there was nothing they could do beyond the update they had applied back in March.