im confused where the o2 sensor needs to go after the cat so that it wont throw a cel. is it after the cat like...


or can it be like this... (im thinking of getting this one and just putting a bolt in to seal up the extra o2 sensor. does that work? need to know where the o2 sensor is supposed to exactly be placed to not throw cel.)


which sort of looks like the official o2 bung carsound cat


For me... living in cali, do i need to get the special cali. carsound cat to pass smog?

thanks.