Writing this on behalf of my dad, we both have noticed an issue dating back to summer last year. All of a sudden, typically while in overdrive cruising along with not much pressure on the accelerator, the rpms would jump to 3k. Now, no codes show up when hooking a scanner to it so I proceeded to clean the throttle plate for him to see if that would get rid of the issue. The issue subsided for a few months, however it is back.

It does not happen as frequently and I have diagnosed it as the transmission downshifting out of overdrive. Now, this should not be happening when the accelerator pedal is not pressed down. It is almost as if the TPS or APP is giving the computer an erroneous signal (as if the throttle is pressed down more than it is) which in turn causes the tranny to downshift. Again, no codes so the ECM must think the inputs are acceptable from whatever sensor is causing this and giving an output signal to the tranny in turn. These electronic throttle systems require multiple sensor inputs to function properly and as wel all know, Toyota's ETC system has major issues. This abrupt "kickdown" should not be happening.

Dad tells me not to waste my time pursuing it any further as he plans on getting rid of the car anyways (the issue will be disclosed to the buyer that the TPS is faulty). Toyota should know however, that this is a major safety issue and wishing it will go away will not make it so. A faulty electronic throttle control system is not something you want to continue to manufacturer...unless of course you are Toyota and put money above the lives of human beings.