I replaced my throttle position sensor today. Was actually pretty easy to do and save me a hundred bucks or so from the shop. Hardest part was that it's on the back side (firewall side) of the intake into the TB. Just needed a small screw driver to get back there and a little patience. No more check engine light and it actually runs very smooth now and shifts very smooth. Guess I didn't really notice it getting worse over time until I have replaced it. Now it's like brand new again on idling, accelerating, shifting maybe even getting better gas mileage now... I think with the bad sensor it was idling a little too high sometimes and that eats up gas over the long run.
I really noticed a difference in shifting from park to D or from neutral to Drive... no noise, or jolt, or anything, just goes into gear and drives away.
Steven, I'm getting ready to check-out the TB sensor on my 99 RX. My shop manual gives the following instructions for installation: With throttle valve fully open, insert the TB sensor to the throttle body with it turned clockwise by 30 to 60 degrees against the fully-open valve position. Then, torque the sensor by turning it counterclockwise.
Did you follow this rotating/torque procedure? I assume you have to do this to make sure sensor does not bottom-out at full throttle.
Finally, can you give me the Toyota part number for the sensor? Thanks.