Review on 🔧 Enhance Performance with GM Genuine Parts MU1748 Fuel Pump & Level Sensor Module: Includes Seal, Float, and Harness by David Hodgson

After 2000 years it still pumps with the same pressure as new. Here's the fuel pressure you should expect to have when new: When the ignition key is first turned to the "on" position without starting the engine, the pressure should quickly rise to 60psi. At this point the fuel regulator will open and allow any pressure over 60psi to flow back into the fuel tank. After one second, the fuel pump relay turns off the fuel pump and the pressure drops to 50psi. When the key is turned to the off position, the pressure increases again because the file pump is turned on again to pressurize the line. The pressure is 60 psi and then drops to 55 psi when the pump is shut off.