Fuel problem

My 1995 jeep wrangler 2.5l drives great for the first 2 miles then begins to go into a short series of sputtering and you can smell the fuel being wasted, until the engine light comes on. When the engine light comes on its stops going into the coughing storms and runs fine until the end of my trip and the car is turned off. My o2 sensor is giving codes saying too rich and too lean. I have replaced the fuel pressure regulator and that didnt solve the problem. Please advise. Thank you!

check your oxygen sensor ,located in exhaust pipe.Befor cat convertor.If its giving a false reading ,your pcm will adjust your timing,air,fuel mix,

A cough and sputter, could be a faulty injector, that is hanging open for a milli second too long, giving you the fuel smell and the rough running. I would recommend remove the fuel rail, with the injectors and fuel line intack. Cycle your key a couple times to get pressure on the line, and see if you have an injector that is dribbling fuel, if so, replace it.