1973 p 1800 es injection problem

I have an unusual problem. My car will start and run, but if you step on the gas even a little, it dies like it is running out of gas. In the process of checking things out, i pulled the vacuum hose off the manifold pressure regulator, creating a vacuum leak. The idle speed increases to 2000 rpm , and stays there for about 2 minutes. Then the car dies. Have to wait a minute or two and it will restart. Also, when the vacuum hose is off, if you touch the accelerator, the car dies. I have cleaned the contacts in the throttle switch, looked good. Also, when the car is running at 2 k rpm. I put my hand on the fuel pump, and when the car shuts down, its still running for a few seconds until the oil pressure drops.Its almost like its running out of gas, or has insufficient fuel pressure. I tried adjusting the fuel pressure but it didnt seem to make much difference. And if it was fuel pressure related, why would it start and run for 2 minutes or so the die? Thanks, Mike