2000 Silverado 4.8 L RPMs will drop at idle, sometimes stalls, sometimes raises back to normal. Anyone else have this problem?

 

Can you give us some OBD II codes? I might help us determine your issues.

 

Check the fuel pressure regulator for integrity - it might have a ruptured diaphragm.

 

My 2000 4.8L would randomly drop rpm and stall at startup. I recently changed the idle air control valve. It was an expensive little part (~$90) but was easy to replace as it’s right on top of the engine behind the throttle body mounted with 2 small screws and nothing in the way. Its been a couple weeks hasn’t stalled since.