The throttle plate is sticking on my 2000 Z 71 with a 5.3 with 60k mi. I have removed the throttle body and cleaned the butterfly and bore so it is sqeaky clean. It moves freely with the engine off but with it running it sticks when trying to move off idle. Very annoying in stop and go traffic. I've removed the cables and the problem is definetly in the TB. It feels like the engine vacuum is pulling it tight against the TB and causing it to stick. Don't know if thats possible! Any ideas? thanks, Stan

 

I've had the same problem with sticking but mine came clear when I used carb cleaner to clean a ring of deposits inside the TB bore. If it moves freely when the engine is off it would have to be the butterfly is closing too tightly. Can you push the butterfly closed with your finger to see if it will stick then? Any slop in the butterfly..... Maybe polish the edges of the butterfly to a smooth any roughness. I don't know what else it could be. Good luck. Let us know what you find.

 

Just take some fine steel wool and clean around where the flap sets at idle. Just enough to have it sit in with no binding.

 

Thanks to both of you. I'll give that a try.