car won't stay running

I have a 1991 lumina with a 3.1 and it seems to be flooding itself out iwas driving and the check engine soon light came on followed shortly by an irratic idle and it eventually flooded istelf out. I took the intake hose off and turn the key on to the ignition position not running and gass slowly seeps out the throttle body until key is removed from the igniton. What is goin on

Pull the codes and post it here. That will give us a good clue at to where to look for this particular problem. Seems like the car is building fuel pressure and the fuel pressure regulator has gone south. Let us know on the codes.