I just picked up a 2000 gmc sierra with a 5.3, the truck has about 215,000 miles but runs pretty good. Im new to these motor and the issue im having is I have to cycle the key once or twice on cold starts.
I havent checked fuel pressure yet but what could be some possible issues? Weak fuel pump possibly?

 

check valve leaking by causing the fuel pressure to drop when the pump is not on.

 

Mine is the same way with 185k miles. Especially if the gas tank is under 1/4.

 

+1 Hook a fuel pressure gauge up and see if it drops as soon as the pump is off.