I've installed a carter P4070 electric fuel pump on my 1969 Plymouth road runner. It is mounted at the gas tank and runs through a Holley Fuel regulator, (which has a return line) and runs to my Carter High pro. mechanical fuel pump then to the carb, which is a AVS2 650 Edlebrock. The problem is the electric pump shuts off once the car is running, I don't know what is causing this, I have the electric pump wired using an oil pressure safety switch and I have good oil pressure. This is the 2nd Carter P4070 I have installed as well as the 2nd fuel pressure regulator, there has been no change, the electric fuel pump shuts off at some point after the car is running, am I missing something obvious? Thanks, 6T9RR