My gas gauge fluctuates from e to 1/2 to f the 3/4 then 1/2 and is never constantly still. 2001 Monte SS

GM has a really bad problem with sending units on the fuel pump which is what is causing the fluctuation in the level on the guage. You should be able to find a new one at your local auto parts store. And that should fix the problem.

Sounds to me that the float is either broken off (rarely happens) or the electronic sensor is malfunctioning. Replace the fuel pump.