Had the same problem a couple months ago. Was solved by new fuel pressure regulator, as the diaphragm in the old one was likely shot. I got mine for about $60 from eBay. Took about 5 minutes to replace. You can check the existing FPR by removing the vacuum line and smelling/checking for the presence of fuel (it should be dry and not smell of fuel). I tried this on mine, and it had a faint fuel smell. The kicker was when I did this and started the car, my FPR was trickling fuel. I'm sure with the vacuum hose attached it was probalby sucking large amounts of fuel into the intake, causing the "flooding" behavior. You might want to look into this.

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