It's happened twice now. I come to a red light, stop, light turns green, I let off the brake, car begins to creep forward just a little bit, I press the gas, and nothing happens. About three seconds go by, then it starts to slowly catch itself and accelerate. It feels like the transmission was confused, maybe somewhere between first and second, not knowing what to do, because I had let it creep just a bit before hitting the gas. But the end result is a bit scary. No forward movement when there are cars waiting to go behind me. Second time in 4000 miles. I would guess this is a programming issue? My 2020 IS350 did not experience such a thing. Today it really got my attention when making a left turn.

 

Happened to me quite often on my 2016. I'd get your transmission levels checked; mine was way off before I did a drain and fill. Not sure if it's placebo or not, but my ride was way smoother after although it hasn't gotten worse that its been 1.5 years or so.

 

It makes me wonder if the transmissions are not filled properly from factory. I even wonder if this problem exists on the IS 500 as well, what with the fairly-common transmission hiccups on that model.

My IS 350 had some weird behavior when cold, too. It would sometimes hesitate to shift out of first gear.

 

The plot thickens. So yeah, maybe there is an issue with the transmission fluid. I will take it in to be check in a few hundred miles.
Just to be clear, the sensation I got those two times was nothing at all. The engine did not rev nor did the rpm's climb. There was just no response from pressing the gas pedal.

 

Now more sounds like a electronic drive by wire TB throttle response circuit issue.

 

Update:

Happened again this morning. Came to a stop, light turned green, hit the gas, and nothing. Pressed all the way to the floor and it gradually engaged a few seconds later. When it finally kicked in, the forward sensation felt like a CVT or rubber band progression. No clunkiness or roughness, just slow acceleration.

Now, I had a chance to break this down further today, and this could be key. Before I came to that stop, I was in D mode, but had used my paddles to downshift. So when I was stopped, the dash displayed "D2" (I avoid downshifting to D1 to keep strain off the transmission). So now I'm thinking maybe the system gets confused because the last "gear" it was in before the stop was D2. Then when it goes to start forward again, it's still stuck in the D2 position, causing the system confusion (?). Of course, I've driven this way since the beginning and never had this issue until now. Just guessing on my part, but I am now maybe seeing a pattern.

Given that new bit of info, what would you all guess?

 

You can use the Gear Position display to see what gear is actually engaged. When using the paddles in D, you can limit the gear range, but you can still enter first gear when coming to a stop in D2.

 

Maybe your gear is still in 2 (or 3 depending on your manual downshift). I’ve noticed that if I don’t come to a COMPLETE stop after using the paddles to downshift, it stays in gear. I try to hold the right paddle for a couple of seconds to put it back in D when I come to a stop.

 

Any message on your dash when this occurs?
Probably unrelated, and you said you let off the brake, but I’ve found (and it’s really annoying and dangerous) that if I still have my left foot lightly on the brake when I hit the gas with my right, the car barely moves, just creeps along. There is a message on the dash about simultaneous brake and throttle usage, but jeez, just go! (2 footed driver, grew up on cars that didn’t idle, and needed a foot on the gas to keep running while at a stop light)

 

When using paddles, I typically downshift to 2nd or 3rd gear when coming to a stop, then it will automatically drop to 1st after a couple of seconds. If you're trying to move right away and still in 2nd gear when trying to move again then I could see that causing the exact issue you are describing.

 

That is exactly what I'm thinking too. The thing though is most of these times, I've been stopped long enough for it to default back to D (more than a few seconds). This last time, it seemed to be stuck on D2. Or at least I caught that on the dash as it was happening.

 

No messages on the dash for any three incidences. One pedal at a time here, but good thought...

 

Correct. It has to physically be in first gear when stopped. But if it's displaying D2 while stopped, the computer may think it's in second gear and goes into a limp mode when I take off? Maybe that's where the "malfunction" is happening?

 

I mean, the "Gear Position" indicator. Not the the thing that says "D2", the actual graphical display.

If you move the tach over, you can select it as a display (or there's even a small version when the tach is in the center).



This is what I mean.

Gears available to you will be illuminated, and the current gear selected will be emphasized. If you have D2 selected, for instance, gears 3-8 will be darkened, and you should be able to tell which one is actually selected.

 

Thank you. Will dig into that and investigate!