2005 Saturn Vue ENGINE CUTS OUT

I've had my Saturn for 6 yrs. Never had any problems with it until now. We were driving down the highway at 70mph when the engine decided to cut out. It sputtered and spit so we pulled over. Sat for a bit and it started and we drove it home. Had it checked out and got 4 codes. 1) Random Misfires 2) Running To rich 3) Running to lean and 4) was the O2 sensor behind the converter. I had the converter replaced, but it's still doing the same thing. Runs good for a while then all of a sudden it will cut out. Any suggestions what to try next?