Just got an IS 250. Transmission shifts fine while driving under normal conditions around town. If I floor it from a stop the transmission does not shift. It just revs up high and redlines. I have to let off the gas when it redlines then it shifts. Paddles shifts work flawlessly and shifts are smooth. This happen in normal "D" mode and Sports mode. This car had a dead battery so I just replaced it. I am wondering if the car is in "learning mode" but not sure if this is normal. Any advice from a newbie?

thanks in advance.

Try this, once again disconnect the battery for at least 20 minutes. Reconnect and then immediately go out and drive the care as you normally would. See if the shifting problem persists.

Report back either way.

Personally i wouldn't floor it right away after disconnecting and battery and reconnecting it. i would drive normally for a few hundred miles. i dont have any evidence on way i feel that way because i just consider it like the breaking in period when you buy a brand new car off the dealer. its learning your driving habits. and aggressive driving in the breaking in period will make it not shift smooth and eventually mess up the transmission. but thats when its a brand new car, after reconnecting the battery i feel like its the same idea but i dont have proof on that reasoning

^But the problem with not driving it how one would normally RIGHT AFTER the battery disconnect means that you miss the entire "re-learning process" of the trans ecu. These vehicles will re-learn in the matter of days; it doesn't take hundreds of miles.

Disconnecting cable again didn't fix it.
Finally got to pulling codes:
P0751: Shift Solenoid 'A' Performance or Stuck Off
P2714 Pressure control solenoid "D" performance or stuck off

Since replacing the solenoids is a hit or miss, has anyone replaced the valve body that includes all solenoids with a
re-manufactured one from ebay or something?

I'm sure someone has, but I don't recall reading about it.

But check this website out when you have a minute : https://www.importperformancetrans.com/

They stock an upgraded IS350 auto trans shift kit; I'm just unsure what model trans you have, but perhaps they have it as well.

https://www.importperformancetrans.com/ It doesn't seem to include the solenoids though so for that price it is steep.

On ebay this is what I found with a 3-year warranty.

https://www.ebay.com/itm/A960E-A960-...YAAOSwYCRdbGSJ

It's a reman, so it's likely just a cleaned and tested OEM valvebody and noids. But the 3yr warranty is good to have of course, in case you start to have issues again. But will that company be around in 3yrs?

Do keep in mind that the trans is reporting what little it knows.
It was commanded to do an action and short of the TCU detecting opens/shorts at solenoid level, it only directs you to a solenoid responsible for an action. So lets say the solenoid is working fine but input speed vs output speed do not detect the gear ratio selected. This points the fingers back to the last command..

Bottom line is if you FULLY TEST the solenoids and they work as expected, your troubles lie deeper inside... They are simply the messenger, not the cause.

Also look this thing over for vacuum leaks....

I will have to look into it more when I get around to it.
thanks...

Just wanted to provide you guys an update, the ebay seller I purchased the valvebody from tried to rip me off but luckily paypal stepped in and I got my money back.

It was this link:
https://www.ebay.com/itm/A960E-A960-...YAAOSwYCRdbGSJ

^What did they try to pull on you?

They stated they shipped the valvebody to me which wasn't true. I asked for a tracking number, they stated I needed to give them my cell #. I provided my cell # several times, and asked for tracking number again. They continued to play this game that they needed my cell number over and over which I continued to provide. I asked them to either give me a tracking number or else cancel my order, they stopped responding. That is when I got Paypal involved.