1995 Regal - Fuel Pressure Problem

1995 Regal, 3.8L, 130k miles. Lately, the vehicle would surge like it is starved for fuel, also is difficult to start at times. Replaced fuel filter, fuel pump relay, pressure regulator. Prior to replacing the regulator, I would hear the fuel pump turn on and the vehicle ran fine. Then starting problem developed, so I changed the regulator (thought that I smelled gas in the vacuum line.) With a pressure gauge connected to the rail, I see 18-20 psi with the vehicle at idle. I still do not hear the fuel pump run when the key is turned to on. With the relay removed and 12V applied directly to the pump, I get 20 psi at the fuel rail with the vehicle running (still do not hear the pump.) Is the pump running slow....that is why I do hear it? Could the strainer in the tank be clogged, that is why the low fuel pressure? I didn't think the vehicle would start with the high pressure pump being inoperative. Could the pump be gummed up and running slow? Is there a low and high pressure pump in the tank? Any help would be greatly appreciated. Joe