I have a 1981 Volvo GLT, B21F (Non turbo) engine with 63000 miles. While searching for a wiring fault that luminates the battery light with the key off, I found that one of the terminals to the fuel pump relay was melted. I have since replaced the relay, but now the fuel pump will continue to run as long as the ignition is in the run position. The fuel pump also makes excessive noise. Is it the fuel pump, the pressure regulator, or something else?