Scnoob

My car scared me twice the other day. My paddle shifter would not let me up-shift under full throttle.

My car is the IS350F-sport non-ML Nebula Grey/Red. My car was in normal mode, traction control off, shifter into manual. I don't know how how all your cars respond, but when I'm in manual mode, regardless of driving mode, my car will still shift up for me around redline, but it I have been practicing using the paddles and the shift *** too.

The scenario was I floored the car at the green light, first gear shifted on it's own before redline, now i was in second gear while keeping the gas to the floor. RPM was climbing and all of a sudden I'm hitting the rev limiter, so I pull of the paddle to up shift; no response. I pull it quickly again all the way mutlitple times and it still wouldn't respond. At this point I was bouncing off the limiter for about 2 seconds so I let off the gas and it finally up-shifted.

What was also was a coincidence was my Nav screen flashed and reset itself. I just got it flashed to 8500 last month, which still sucks as we all know. Last night after work I tried to simulate the issue, the car is still shifting on it's own, but the transmission shifted kind of rough into third with a soft clank. I'm calling my service rep now.

Yes my car was warmed up. My car always shifted by itself in manual if I never intervene until these last few times My miles are over 8500. I always run good premium gas. I don't know I'm doing anything wrong.

My appointment is tomorrow for my navigation and my paddle shifter. Ugg...

TheShaddix

Maybe you've already tried this, but I would try and unplug the battery negative for a few hours or even overnight, I've read on other car forums that helps with issues like these. The ECU will then recalibrate itself and should be back to normal. It's worth a try.

phungy

Same issue. When I go full throttle and try up-shifting on either paddle or shift ****, it wouldn't respond until closer to redline.

NYKnick101

Under Full Load/WOT the cars computer would hold the gear and shift at an optimal rev range. When using the paddle shifters, sometimes you would notice that if you shift too early at WOT and it will still attempt to redline. If you shift too late past that optimal point, it would hold redline until you take your foot off the gas for like a second. Its kind of normal because paddle shifters doesn't make the car completely manual, there is still a computer controlling it all like standard automatics. Even if you are in first gear and you redline it too much and never upshift, the car will up-shift it self into second gear (with out touching anything)

I don't think the car is the issue, I think thats just normal and you getting used to triptronic. Plus regular D shifts the car much faster that using the paddle shfiters.

TheShaddix

No, this isn't normal... In manual mode it should shift instantly with just a minimal lag, doesn't matter if you shift at 4k or 6.5k right near redline, it should just go into the next gear instantly, even in ECO mode. However, in drive mode, while using paddles (D1, D2, and so on), it will shift when it wants to regardless of what you do since shifting in D manually is just limiting the gears it can use (temporarily)., but in M (shifter to the left) it should be completely overridden and not hesitate one bit. Previous IS models didn't have this, but the 3IS 350 fsport with the ISF transmission should shift the second you pull that paddle. This is how mine is, and both the ISF's I've driven. Have the dealer tech look into this, don't assume this is normal just because someone else is saying it is. And at the last resort, try the battery trick.

NYKnick101

Its definitely worth looking into so going to the dealer I would agree and suggest that but unless the transmission is bad, my bet is gonna be they will send him home saying everything is fine. If you google "Paddle shifter delay", i guarantee you will find forums across every car brand saying they have the same issue on how its not fast enough and there is a delay before the car actually shifts under full load. Down shifting is seamless and does it instantaneous but the problem that automakers are trying to fix the up-time shift with out creating a JERK in the car but Trip-tronic transmissions have come a LONG way. I just drove home from work and foot to the floor, i can count almost a whole Mississippi before i see the needle drop.

I will say definitely try the battery trick and then see how the car reacts to relearning its driving patterns. All that other stuff is just a coincidence. But like i said, paddle shift wont give that instantaneous shift as a true manual car. At the end of the day, its still an automatic

dojoman

iTrader: (5)

Even in automatic it will hold gear a lot longer at WOT. Just like NYKNICK said it could be normal behavior for this car. I hardly use M anymore since transmission is so good in auto.

TheShaddix

Yes, there is a delay between the moment you pull the paddle to when it actually gets into the next gear, it's not dual clutch, obviously...But in each gear this delay is different. However, the car (at least mine) never hesitates long enough for the RPM to get into the redline and hit the rev limiter. For instance, first to second shift, no matter what rpm, is instant, absolutely no delay. Then second to third it still starts shifting right away, meaning the actual process of changing gears when you pull the paddle, but takes a bit longer to get into the next gear due to it not being dual clutch. However, it does not let the RPM climb while that shifting is happening. And the rest of the gears is even quicker. Either I'm completely misunderstanding what you guys are experiencing in your cars, or it's possible that I just don't wait long enough when i shift for it to go into the redline? I shift around 6.5k rpm, basically whenever the needle gets right to the red line. And what happens is it immediately starts to shift, even if there is a slight lag in the process, but it doesn't let the car keep revving up and then shift by itself. Also, this might not be news to you, but you have to make sure your car is fully warmed up. If it's not, it does not let you shift manually and also limits the RPM's. And that's about 5 miles of driving to fully warm it up, and more in colder temps...Don't forget that the temp of the engine has nothing to do with the transmission. Disregard if you already knew this. Does this issue happen even after a long drive? Just trying to understand it better i guess. And I gotta disagree completely about the downshifts...They are anything but instant and smooth...They are probably the worst in this car. It does downshift smoother if you either let go of the gas, or give it more throttle. But not when you're just sitting on gas, cruising, and when you downshift, it will be jerky.

Scnoob

Update real quick before I go to work.

Yes my car was warmed up and etc. I wouldn't do that kind of abuse to my car. Honestly....

Now for the news I got back from the dealer. My head unit was causing problems (flashing etc.) and was throwing codes to the ECU and black box. It turns out the Multi-Trac system for the transmission is also linked to the Nav system. So it's possible my paddle shifters didn't respond when the Nav was having issues at that time.

Lexus said they have no official fix for the head unit, until they actually have the Nav unit crash in the shop. So if it happens, they want me (you guys can do it too) to record it on the phone, bring the car in for immediate code retrieval. The car loses most codes after a few key cycles.

Have a good night. Time for me to go to work. Night shifts working in a Trauma 1 center are never boring.

JGard18

Very interesting to hear about the nav unit tie-in. I can say my paddles have not responded a few times, but it's typically been when the engine is still cold. And I'm not flogging it at the time, either, just casual acceleration.

However, I cannot get my car to redline. In fact, I've never seen it rev to even 6,500 RPM. Even in M mode, no matter which gear I'm in or how hard or soft I'm on the throttle, my car will shift once it hits 6,300 RPM.

I will be mentioning this when I bring it in for the 5k mile service in another week or two, as I don't think it's right. I want M mode to be 100% manual, no automatic upshifting, ever.

TheShaddix

And I'm assuming that's with the car fully warmed up? Like after 10 miles of normal driving? When it's not fully warmed up, it will shift earlier. And I don't mean when the engine temp gauge is in the middle. Transmissions take a while to warm up fully unless you're constantly shifting.

JGard18

Yep, it'll be after a solid 20 minutes of highway cruising where it does this.

TheShaddix

Another possibility could be that the ECU has learnt your driving habits and shifts early for you. Do you drive aggressively often (full throttle runs, late shifts, etc)? If you drive mellow all the time, there is a chance the ecu just optimized itself for that kind of driving. Might be total bs, but that's what I hear some people say. If you care about correcting it, unplug your battery negative overnight or so, then when you get back in it, warm it up and drive the way you would want the car to drive, that could fix the issue. Every time i unplug my battery for a few hours doing some new mods, I notice the shifts are really odd and the car feels like it's adjusting again, then after 10 or so minutes it's all good. See if that does it. Btw, trust me, you do want it to eventually auto shift for you. So many times I forget i'm in M at a light, then it just hits redline and you're glad it shifts for you. In my car, when in M mode, it feels manual enough to be fun. When it's fully warmed up, it always gets to redline before shifts. But I drive like this pretty often, as well as in eco mode. I'd say about 70% eco and normal, and the rest in sport+. I don't bother with just sport, I dont see a point in lexus having that option when they know well enough that people will go straight to sport plus.

Slust

^^^
The ECU does learn your behavior. Both my co-worker and I have noticed it with our 2IS. When he lets his wife drive his 2IS 350 she gets 27mpg for a few weeks but when he gets it back it drives SLOW as hell and he has to re-teach his car to shift the way he wants ...and then he gets his standard 22mpg. If I drive like a normal human being, the car will shift conservitively even in Power mode (2IS) or Sport+ mode (3IS). I usually brake the cycle by switching into Manual and doing a full drive or two that way. The next day the car will almost always wake up and then beg me to floor it and have more aggressive shifting.


Automatic shifting is standard in all fully auto cars that offer a manual mode. BMW and Audi are no different. They do it to protect the engine and transmission, and its smart for the very reason TheShaddix says... People get used to driving in fully auto mode so when they do switch to manual their mindset isn't, "If I don't shift I'm blowing a tranny and possibly an engine." Their mindset is purely set on fun, which can be fleeting ...especially if the traffic pattern changes so they can't race like a hellion. It's very easy to forget you're in manual mode. And if you blow a tranny or engine, who usually gets the fault? It's NEVER the driver's fault, it's ALWAYS the car. So blame all the lawsuit happy individuals that ruin everything for everybody.

jat0223

iTrader: (1)

I agree with mostly everything you wrote except this statement. Not all auto cars do this.