HI,
I am working on my 97 Contour Ztech, I have a scan tool thing and am getting a 171. Supposedly a bad O2 sensor. SO I check them and it says sensor 2 is giving no response. Well, logic would say I guess that 2 is after the CAT. The other sensor is reading the way it should, so I would just as well return whichever sensor I do not need to replace (bought both before store closed tonight since I need to have this thing good for work tomorrow) if anyone knows which sensor the scanner thinks is 2 I would greatly apreciate a response.
Thank you
