1999 Toyota Harrier cant change gear 3 to 4

Hello Drhkksoe,
i had the same Problem for many month (2 4! )And spend a lot of Money by My Lexus Dealer, Transmission Repair Service a.O.) But in the End "NO RESULT!)
I got on all Lexus Sites in the Net. In the End, I found the same failure, and he chanched the 2 Knock sensors and the Problem was solved, so I orderd the sensors in the States (i am from Germany, but the car was Imported from the us in 1999!) The sensors cost about 25 % from the German Price, so I buy also the 3 Lamda sondes. After 5 days my Parts arrived and a friend changed the Parts. The End of my Story, the car runs absolutly perfekt, after the replacement of the Knock sensors (The car changed the Gear 3 to 4 after about 3 to 5 Minutes when the temperature is ok!) When the car is cold in the morning is takes some time to get the 4th gear, but its ok (telephone with Lexus Europe)
So get the Knock sensors (its a little bit difficult to change the Parts, you have to remove the cmpl. Zyl. Block, on the Bottom are the 2 Sensors.) When you order the sensors, get some repair manuals for your car also!)
Frank