1990 Pontiac 6000 3.1l starts and stalls

1990 Pontiac 6000 LE 3.1l engine stalls after it runs a while
I have a 1990 Pontiac 6000 with the 3.1 multiport injection. When the car is cold I can start it and let it run for a while. After the engine is warm for a bit the car will stall out. When I try to restart it, it will sorta start but shut right down. I have good fuel pressure and spark and injector pulse. I also cleaned the pcm ground wires at the trans. The interesting thing I found is, if I disconnect the injector connector to cylinder #6, the engine will run and stay running. Once I plug the connector back in to the injector it stalls right out. Then it does the same thing where it starts and as it goes to rev up it stalls out. I replaced the crank sensor already as well. I don't think it's the module because when I check for spark I have it. Also, I don't think if it were the module that the engine would run by disconnecting the injector connector. I don't want to keep replacing parts. I have a code 33 present, but I think that is fron running the engine with the injector disconnected. Can anyone help me?