1987 Pontiac Sunbird 2.0 liter car just died on the road

1987 Pontiac Sunbird 2.0 liter mileage: 110,000. Problem occurred a few months back when car just died on the road we had to get it towed to the house. 3-4 months later, we decided to work on it. We replaced head gasket, manifold intake gasket, plugs and new wires, pickup coil. Now after the battery is fully charged when we try to start it, it takes around 5 minutes to start. After it is started when you press the gas pedal it makes some noise like bup, bup then tries to catch up and dies. You can start it again but as soon as you give some gas it dies, then you cannot start it you have to let it stay for some time then put some starting fluid in the intake and start again and then the whole cycle repeats again. We are thinking of replacing the oxygen sensor, because the computer is not showing any codes. Will replacing the oxygen sensor solve our problem? If not what should we do?