2003 Pontiac Grand Am engine

I'd check fuel pressure, not only check for correct fuel pressure, see if fuel pressure will hold for a bit with everything off. If the fuel pressure regulator has a vacuum line on it, check to see if any gas in the line, shouldn't be any gas in that line.

Check for injector leak. The coolant temp sensor can cause it to flood? Can you check for applicable trouble codes? To check codes, yourself, at the least, you need an obd2 code reader.

Did you use a fuel pressure gage on it? 50--60 psi. Some of the national brand auto stores will loan out a fuel pressure gage, you may have to put up a deposit? Those stores will check trouble codes for free. I've seen a clogged return fuel line cause pressure to go high, where applicable.

With everything off, The fuel pressure shouldn't drop more than 5 psi in a minute. If the pressure drops like a rock, you have a leak.