Ok, so let me tell u the symptoms that i experienced. This happened in the midst of summer, we get mid 40deg temp here.
When i slow down to a complete stop, when the gear downshift from 2nd to 1st, its a big jolt and when it comes to a complete stop, another jolt.
Went to a transmission specialist, gearbox pulled apart, no problem with hardware, filled up with fresh toyota transmission fluid and went for a drive, problem still exists.
Both the transmission guy and I did searches online and found out its the ECU that is causing this. He rang up his contact in QLD (i need to find out who the ECU repairer is) and apparently he had fixed a few Lexus that had the same issues and its definitely the ECU.
Sent ECU to QLD, after a week got it back, fitted it back on the car and it drives good again.
All these messing around:
All up costing me $2337.00 , repairing the ECU was $900, the rest of the cost are stripping gearbox apart, putting it back together.
Incompetent Lexus of Perth wanted me to get a new gearbox for 13k or a used gearbox for 7k, thank God i didnt trust them and went to a transmission specialist instead.