with a new converter and running the afc lean and your still failing it sounds like it MAY be a bad o2 sensor.

the o2 sensor can be bad and NOT set the check engine light. i see that happen ALLOT.......

also check to see that the engine is getting up to operating temperature. make sure the engine coolant is toped up. the engine has to be hot and converter fully warmed up to get the most accurate readings.