i have a 94 silverado with a 350, its tbi. when ever you rev it up to around 2000 rpms, and let off, the rpm's kinda flutter around for a sec, then drops, but when you floor it, the rpms drop when you let off.

if im not explaning this right i can take a vid of it, but anywase if you know what im talking about is this normal?

How many miles are on it & when was the last tune up? Have you ever changed the fuel filter?