Well i just put the hotshot header on my car a few days ago. Runs great but a few days later i got the dreaded "service engine soon" light on. Now i know why it is doing this. What i would like to know is there anything out there that can trick my ECU into beliving that the o2 is actually reading the exhaust after the cat?. Is it just wiring? or an actual different o2 sensor? I do not want to have a damn o2 bung welded after the cat. SO PLEASE let me know if there is something out there or how i can fix this problem!!