Pontiac Repair: 1991 Pontiac Grand Prix Flooding and stalling, fuel pressure regulator, pontiac grand prix

Question
Wayne I need HELP!
1991 Pontiac Grand Prix 3.1 L  130,000 miles.
This problem was spiractic and now The car will hardly run any time.  If you can get it to run it will just flood and pour black smoke out of it and I noticed I pulled the oil dip stick out and its nearly diluted with gas.  I changed plugs and wires and fuel filter and air filter.  Ran some fuel injector cleaner through it. I checked fuel pressure at the rail turn it on shows 38 psi.
If I try to make it run much more its going to self distruct wild as it is.  Any idea why this will not run
and run so rich.  This is a widows car and I am trying to fix it out of the goodness of my heart!
Please help am Desparate.  I would be indebted to you for life.     Sincerely  Jeffrey D Price

Answer
Jeffery you are a good person for doing this. lets start with the fuel pump, when you turn the key on how long will the pump run? it should not run no more then 3sce. if this is ok. The next thing would be the fuel pressure regulator, Key on engine not running the pressure should be around 41 to 47 psi, with engine running it should decrease by 3 to 10 psi, To check the regulator the engine has to be running, with the tester connected disconnect the vacuum line on the regulator the pressure should immedliately increase by 3 to 10 psi, if it dont the regulator is bad.
The next thing would be the 02 sensor it should set a code, and the check engine light would be on. And the big one the ECM is bad and cause it to flood out.