Throttle body grinding: Anyone had this issue before?

[MileHigh18]

For the past couple months when starting my 02 Trailblazer, I heard a grinding noise. I immediately though it was the starter, but it didn't sound like it was. So fast forward to a few days ago, and I get the SES and REP lights and limp home. I pulled the throttle body and give it a good cleaning, though it was still pretty clean from when I did it in March. I just happened to hear something rattling around where the throttle position sensor and stepper motor are housed. It sounded like a piece of metal or something had broken off and was floating around in there. Also when moving the butterfly gently by hand, the whole thing made a rough grinding sound as well. So needless to say I replaced the tb and all is now well, but I've never seen a tb fail in this manner. Anyone else?

 

[kickass audio]

I had mine do somewhat the same thing. Mine however had a bad tooth that sometimes would slip and jam the throttle plate up in the throttle body. Sometimes it would jam and set the SES code, other times it would jam and you knew it because the acceleration was very slow and it would then catch the gear and open up more to continue normal acceleration. The TB was never cleaned prior to me owning the truck so I am 99% confident that it broke from the old oil blow by that caused the TB to gum up and jam itself, causing the plastic gear to snap. I now clean my TB every year for good measure and have not had a problem since.