I have a 86 mustang with a 351 650 holley with a electric fuel pump. Recently it starting acting up. I turn the key to on and you can hear the fuel pump running and the car will start but the fuel pump quits working along with the tack and radio. It will run until it runs out of gas in the carb. I can turn it off and then back on and you can hear the fuel pump running until it starts again and then all quits. After a few tries the pump stays on and the tack works along with the radio and the car will stay running until I turn it off. Anybody have any idea what is causing this?

 

Sounds like the ignition switch is going bad, do the dash functions and dash lights that quit- match up with turning the key off?