Q: Fuel Pump Pressure intermittent 2001 Chevy Silverado 1500

Hi there - you have a failed or leaking fuel system check valve. This valve is designed to maintain low, positive pressure in the fuel system. This allows faster starts first thing in the morning, requiring the fuel pump to run less building up adequate pressure to fire the injectors. Since it leaks down, the fuel pump has to work longer to build pressure. This check valve may be part of the fuel pump assembly, or the fuel pressure regulator assembly. I would recommend an inspection of the fuel system by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.