So my 02 Mustang GT has been a complete nightmare from day one. The person I bought it from wasn’t kidding when he said it was “bone stock”. I knew what I was getting myself into to an extent, but it seems this car just likes to fail. So, out of the many issues I’ve had this is one I need help on. When my car idles from a cold start, the o2 readings on both rear banks are good. After there’s heat in them they ping pong and are no longer consistent. I am pretty sure this means the converters...

Bad catalytic converters?