thanks for the info. I might get the GReddy ground kit and stabilizer off ebay for $56 and try it out. that kit has the round metal piece with a number of wires coming off it that all hooks to the negative battery terminal which sounds like hyper grounding system. but yeah when i get my new cat installed ill have a new 02 sensor also and then later on ill put a new one in my header when i get my new dc sport 4-2-1. Ill try resetting my ecu and see if it goes away.