no! I did not touch the upstreams at all!!
What i did when i went catless, is throw on mil's on the downstream o2 sensors. I have a cougar, and i have 4. 2 per manifold. Since i was pulling a code on the bank 1 sensor 2... the downstream sensor nearest the firewall, i swapped out the mil wit the bank 2 sensor 2 o2 sensor, which is the downstream sensor near the radiator/lower radiator support, hoping the mil was the problem, and when the CEL came back it would show it on a different bank. The code came back to the same o2 sensor... bank 1 sensor 2 near the firewall, after i switched the MIL's
this is why i believe the mils arent the problem, its either in the o2 sensor, wiring, or something else i have overlooked. Does this help clearify ray? But i dont understand if i have a mil on the o2 sensor, how i can still get a cel from it.
