My Cel light stays on constantly ! Its throwing codes 1 & 12. 1 being the o2 sensor(my focus) and 12 being EGR(I have a auto ecu in my 5spd). I swapped in a new o2 sensor and reset my ecu last weekend and nothings changed. Light comes on as soon as I start up. I tried grounding the shielded wire and connecting the center wire to the o2 but I still have the same results. I’m stumped ! I don’t have to smog until next December but I’d like to have this fixed by then.
Its a 90 Teg Ls with DC headers and ebay catback.