1994 Supra Sunsport/Pro Boss 300 Fuel Problem

I have a 1994 Supra Sunsport with a Pro Boss 300 engine (351 Ford). We have experienced intermittent fuel flow issues lately (three times the last four outings). After sitting for a period of time, when trying to restart we get only trickles of fuel from the injectors into the throttle body. My fix has been to lightly tap around the fuel pump with a small hammer. I’m not sure if I have a pump problem, an electric problem or a filter problem. Any suggestions would be appreciated.