So looking back a year ago it looks like this could have been the start of my fuel pressure regulator problems. My brother came to CO in April, and I fired up the engine for him and it was popping out of the exhaust and running rough. I didn't do much with it after that until I tried to get it running better to charge the A/C. Now I know the fuel pressure regulator vacuum line was pouring fuel into the intake.
That brings up a question. I have been told to remove the vacuum line and that you really don't need vacuum to the regulator. I know the vacuum changes the fuel pressure with respect to ambient pressure, but keeps it tied to manifold pressure. So as manifold vacuum drops, the fuel pressure rises. But it seems like a constant pressure relative to ambient would be better, and you can just tune the system to the correct for the added pressure at idle.
I'm not sure whether to hook up the vacuum line or not, and I read conflicting things online about it. if I didn't hook it up it would prevent the problem I had with the broken diaphragm and flooding of the engine which would be nice.
Any advice or comments on this?