Hello Scotty,
About 10 months ago, I bought a 2006 Lexus is250 RWD auto with 193k miles for $3,800 from a friend. Even though it had the code p2757 for a transmission solenoid ($30 Autel scanner), I pulled the trigger because when test driving it the transmission was ehh but it worked well enough for my daily use (periodically had minor shaking into 3rd and rough downshifts). Additionally, my friend had been driving around with that same code since about 185k miles and he said it has not gotten better or worse. The code would show up intermittently, about every 300-500 miles.
After buying the car, I had a Japanese auto mechanic take a look and he advised me to flush the trans and change the corresponding solenoid with the code. This actually helped the issue but did not completely fix it. Now the code would show up about every 1000 miles and shifts a bit smoother. I also carefully cleaned the throttle body of carbon buildup.
However, the car still has issues shifting, especially from 2-3 gear and downshifting 2-1. The car drives normally for about 15 minutes, but once it warms up it shudders into 3rd, and downshifting into 1st it feels like there is a bump in the road. Freeway driving is where the car is most happy.
Now the weird thing is this issue only happens half of the time. If I drive the car especially hard, the issue magically disappears. Additionally, I've found the more I drive it and turn it off and on during a period of time, the smoother it drives and sometimes the issue vanishes completely only to appear the next morning again.
I am now at 205k miles and honestly the way it is driving, I would say it could last tens of thousands more. I have taken this car up Mount Hood and back, through the Coastal range, and Portland to Seattle with no issues—other than the ones I stated above. With the symptoms my car is showing, I really do think it might be a computer issue because as it turns out, it is a common problem with the 06 year according to the forums and requires changing or rebuilding. What do you think? Thank you!!!
After a new solenoid and fluid and filter, the torque converter is probably going out.
Definitely a possibility. If it is bad, probably will not worry about it because it is still reliable. Still stumped though by the fact that it will drive perfectly sometimes and other times not :/
Unfortunately I have referenced that website above. My mechanic went as far as cleaning each individual solenoid, doing a second flush, and checking all the relevant wiring. The only thing that hasn’t been checked is the computer (ecu) itself :/