1990 Oldsmobile Cutlass Engine Dies

I recently bought a 1990 Olsmobile Cutlass Supreme SL with 55,000 original miles when I start the vehicle wether driving or idiling after 10 - 15 minutes the engine will die and it will not restart for two to three hours. I have replaced the catalytic converter, I have checked fuel pressure, and I am not getting a check engine light nor am I recieving trouble codes. The vehicle was purchased in Illinois, and brought to Colorado. My mechanic and I are both stumped any help would be greatly appreciated