Hi everyone,

I’m experiencing a strange issue with my 2006 GS300's transmission and could use some advice. At low RPMs and barely on the gas pedal, I first noticed this while driving through freeway traffic and another at a parking lot at a very slow speed. When accelerating from a stop at low RPMs, the car shifts from 1st into 2nd smoothly but then immediately shifts back down into 1st, then back up into 2nd, and repeats this cycle. This continues until I either let off the gas pedal or apply more throttle to power through it, at which point it shifts without any kicking, hard shifting, or rumbling.

If I anticipate this happening at a stop, I can throttle into it a little more, and it will shift completely fine. This issue only occurs at low RPMs and doesn’t require wide open throttle to get through it—just a bit more than parking lot speed. Once it shifts, everything is fine, and I haven’t noticed any other issues.

Has anyone else experienced this? Could it be related to the Throttle Position Sensor (TPS) or something else? Any advice or suggestions would be greatly appreciated!

 

So many of these...

Same or similar issue as the other users. Search the forums before posting. I had this same issue and fixed with the ECU repair for $150.

https://www.clublexus.com/forums/gs-...n-problem.html

https://siaelec.com/product/15410/

 

Hey Tres. Thanks for your comment.
I wanted to give an update. The car would also stall every time I go from drive to reverse after driving for a while; it doesn't happen in the morning when I start the car.
I had the ECU reprogrammed, but that didn’t resolve the issue. I ended up swapping in a used transmission from the same model with lower mileage and that fixed the problem. No idea what was wrong though.