There was this butthead kid in a big ol Dodge truck you know the 4 inch turbo diesal exhaust pipe hanging out the back? Well he gets in front of me and keeps romping on it blowing huge clouds of black right in my face, (were on the freeway doing about 65) so I try to pass the beeeoch and he floors it thinking he can beat me, well of course he didnt stand a chance and I blew by him no problem. But now the Stang is idleing rough, slight knock at varying RPM's and egg smell from the cats. I didnt hear any kabam! or anything just runs like crap now... any ideas?? Thanks... Oh yea, spec info... 2K 4.6 2V, Series II, 66mm chicane pulley/RipKit, SVT Focus Fuel pump.