These would be the pre-cat sensors, the one's you need to have. If it's throwing a code, then the O2 on the drive side is going bad. You can replace just the one...but if you're like me, you do it in pairs. Just makes more sense.

If you wanted to make sure it was the sensor and not the wiring, swap the passenger O2 with the drivers. If it then throws code P0154, then you know it's the sensor and not the wiring. But I'm pretty certain it's the sensor.

 

well I really messed up then. I installed the simulator on these sensors, what will that do, is it going to wreck something? It is strange because it is still doing the same thing as it was before the simulator. That is what confuses me the most.

 

You should not install sims in your pre-cat 02 sensors. You need the front sensors to work properly in order to get the proper a/f mixture.

 

Does anyone know where the sensors should plug into on the plug side, not the sensor side? and I guess I may just have a bad sensor and I should take the simulator off.