My car has lately been running super rich, I mean at idle it is anywhere from 10.0 to 12.2, also when I'm crusing down the highway it is exactly the same way, I have noticed too right after I fill up the gas tank that at idle it literally sits at 10.0 for a while and is running so rich it sounds like it has bigger cams....my mod list is this

Injen UICP/LICP
Spooling COP Kit
Evo 9 10.5 turbo
Turbosmart 22psi wastegate
Bushcur TBE
Megan o2 housing, Perrin intake filter
Injen intake
Aem wideband
Aem boost gauge

Fuel pump and injectors are both factory and car is still on factory tune.. Any ideas????

 

All these mods and no tune? No wonder your car runs like crap. Get a tune and get your money's worth out of your mods.

 

Front O2 sensor most likely.

 

force the car in open loop and see if it is closer to stoich. if so front o2 would be poop

 

x3 on the front o2 sensor. just replaced mine and car ran alot better as far as afr readings..