So i have been trying to solve this o2 sensor problem I've had for a while now. Any sort of diagram for the wire colors or pinout schematics always has different wire colors and I cannot for the life of me figure it out. Can someone give a dumb'd down explanation of how they are routed. I have a diagram of the NGC and I am going to use that to try to figure it out but I just dont know what each color is. I am kinda new at all this but I am determined. Finding ground pins at the o2 connector truck side is obvious but I have 1 wire that foes from one connector to a connector that is by the air filter and hood lifter shock. It doesnt go to the pcm. It goes up and all the way over towards the battery which I believe it goes to the fuse box but I did a continuity check and nothing. Also why is there a relay for o2 sensors but it says in (8.0 only) I believe? I also checked continuity at the fuse too and once again. Nothing. Basically at the beginning of working on this truck I had no idea what I was doing so I (regrettably) cut the connectors one day because I was told to try to disconnect them to solve my misfire. Well it solved the misfire but has been giving me terrible mpg and just runs like ****. I just want to get it taken care of and my engine light off.

 

Have a look here. See if that helps at all.

 

Where did you make the cut on the O2 sensor wires? It seems you could splice the wires at the cut vice tracing them to source.
What is your current setup with regards to O2 sensors? Are they plugged into the cat and not connected? Do you still have the plugs that were at the ends of the O2 sensors, and, the truck side of the O2 sensor wires?

 

Thanks that was exactly what I needed and will use the site for other issues too.

I'm starting to think my pcm is bad I still lam getting codes after everything was connected correctly but as to answer for my setup I have lt headers no cats true duals with mufflers on both pipes. Front o2 sensors are in but been trying to figure out what I want to do with the rear sensors. I hate the engine light. But I got a superchips tuner that ended up taking a **** on me it will no longer read thr trucks pcm. Comes up with communication fail. Now I have a engine coolant temp code along with the lightning bolt just after I replaced my broken bolts to my intake manifold. Odd that they both came up. I had the throttle system light come up about 3 months ago and replaced the throttle body and that took care if the light. But now it's back on which is weird. Also I recently read that grounding the throttle body can benefit the engine so I did that but havent noticed much of a difference tbh I'm going to go check my grounds now just to make sure along with other potential mistakes I made but I am usually pretty good at checking over 3 or 4 times so I dont make them mistakes