When the pm5 is in i dont throw any codes but when I put the pm6 in I threw code 4 and code 16. 4 being the cas and 16 for fuel which i believe has everything to do with me not having mpfi. So for the time being I put the pm5 back in. Hopefully this weekend I will be doing the mpfi swap, my only hang up is that I found out about an hour ago that I need the si engine harness. As far rich or lean, nothing noticeable is going on.