2013Fsport, at the moment I have done the Throttle re-learning process 5 times in total start to finish, right now it won't even idle less than 1000rpms. Even putting the car in gear it still idles at 1000rpm, and throttle response is still non extistent. the only thing i havent tried yet and a couple people have said it isto disconnect the battery for a minute press the brake pedal a few times to remove residual charge the reconnect and let the throttle and car re-learn itself. Which i'll give that a try in the morning.

 

Are you sure MAF sensor is connected and working properly?

 

This thing should have lit up the dash with throttle actuator or throttle motor errors. Do you any kind of code reader?
There are 6 or something signals that can be read and viewed regarding the the interaction of the pedal and throttle body.

Did you look for rodent poop? Unplug anything?
Did the engine upon first start rev to 1500 or so?

 

Get it to a Lexus or Toyota dealer for them to diagnose it for you.

 

I dont have a code reader, but I will say that prior to the car having the 2nd to 1st hard downshift issue the car even ran perfect and drove great inspite of the known lights on the dash pertaining to not having any tire sensors, but since having the car serviced at the only dealership an hour away and spending almost 5grand, my next thought is to disconnect the battery as i had mentioned and then let the car do it's thing, cross my fingers, cold beer at the ready! and see what happens LOL !!. but i am gonna order up the number 1 solenoid for the trans and replace it and then maybe get ahold of my cousins buddy who does a lot of computer stuff for dealerships around the area and see if he can fit our car in.

 

been there done that! and the issues it did have and may have had they didnt say.......on top of the almost 5 grand spent there.......Not going back since they didnt fix anything!, but they were sure happy to get us into another "IS" ! LOL

 

The ECU needs to be rebuilt by SIA Electronics.