whats up my fellow x type homies, do any know where the upstream 02 sensor is located found one but cant locate the second one. it will be greatly appreciated if someone can drop me a line or pic tx bros.

 

There are two upstreams and two downstreams. One of each for each bank. Which are you looking for, bank 1 or 2? One O2 is screwed into the cat converter and the other is right next to cat on the exhaust on both banks

If you found one already, just follow the wiring from the harness. The harness plugs are right out in the open on both banks. One set of plugs is back on the firewall by the brake booster and the other is up front in the water pump area by the battery box.