Chrysler Repair: 1994 Chrysler Concorde O2 Sensor, o2 sensors, chrysler concorde

Question
My check engine light comes on after a few miles. I checked the sequence and get a 21.  I have looked everywhere online but can not find any info on how to located the O2 sensors. Do you have a diagram or specific instructions on where to find them?  Is this something I can replace easily?

Answer
Yes you should have either 2 or 4 o2 sensors and they are the only sensors located on your exhaust. you will need a 7/8 wrench or a special o2 sensor socket to remove them I think your vehicle has 4 so depending on which one is bad it should say something like bank 2 upstream or bank 2 downstream or bank 1 up or downstream and what this means is your bank is the side of the cylinder head exhaust that the sensor is bad so if it is bank 2 it would be on the cylinder with spark plug 2 on it and if bank 1 it would be the side with cylinder 1 on it and upstream means the sensor before the catalytic converter inbetween the cat and the engine and if it is downstream it would be after the cat so between the cat and the muffler these sensors are normally very difficult to remove they are very tight from the heat