Cammed4ever

hey guys, first of all, my best friend used my truck like 6 months ago and he messed up with my trucks stereo and unplugged the XD-16 monitor and he plugged it back in the "out" line instead of the "in".. anyways when I had my truck back the XD-16 monitor showed "-.-.-" and I never knew what happend and didnt have time to mess with it.. (that happened like 6 months ago) so, a week ago I was messing with my stereo installing and equalizer and found out the problem.. (was connected in the OUT instead of the IN plug..) fixed that and now the XD-16 is giving me some numbers but its all messed up.. at idle it shows AFR around 8.6.. and when I go WOT it shows E 8 Im guessing Error 8... Does somebody know what could happen during those 6 months, or does it only need recalibration??
Thank you so much!!