kilkenny,
You would probably get a PO420 and a PO430. I was getting these codes and added MIL's and the CEL hasn't been on since(knock on wood). I added the MIL's about three months ago. I didn't gut the cat but I asked a guy at a shop about MIL's and he said that the MIL's would take care of that too. Hope this helps.
Later
