I have a quick question. When i put my full magnaflow cat back system i noticed the o2 sensor is before the cat. Does’ suppose to go after the cat? Also i have OBX headers meaning no pre-cat. No check engine code came up for like 3 month now. Does it affect the engine performance? It seems that the second 02 sensor is reading the same numbers as the first o2 sensor the one on the headers. Any advice? thanks
This is for a 02 2.4L