Hey guys, just put long tubes on my car last week and it seems to me that the car is running rich for some reason. The only thing I have changed on the car is the headers, I also added the NX plate kit, and I made my own rear O2 simulators. Any ideas on what to look for? Could an air leak from the plate kit cause it to run rich? Could the O2 simulators be causing it? Or is it just normal after putting on the headers? Any advice is appreciated, Thanks!!

 

have you listened for exhaust leaks?