High Pressure System
WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The much larger section of the fuel injection pump assembly is the high-pressure pump. The pump is engine-driven by the camshaft gear. From the high-pressure pump, the fuel flows to the 2 common fuel rails. Each common fuel rail supplies one bank of 4 fuel injectors.