Did you take the cover off to see if it had bad gears?
I saw
this, which claims to be for our part number, but I'm skeptical.
A couple of questions about replacing it that prevented me from trying to take it off to remove the stuck screw on the TPS:
Do the ball joints on the arm to the throttle rail just snap on/off?
How much of a PITA was it to get to the bottom bolt?
It's behind a wiring box that's behind other things and looks like it would have been a real pain to remove. I'm guessing at least one of the screws that secures it is inside the box, so I have to open the cover, all the plastic tabs will crack off, ...