Having trouble finding 02 sensor after the cat converter. Getting check engine light. I can find 2 sensors located at base of headers, but cant find one post cat. I don't believe the cat was ever replaced in the past... One thing I find interesting is that there is a wire clip located next to the back of the cat, as if this is where the sensor wire would go. The clip is the same type as the one used for the front header o2 sensors. I believe that the codes pointed to a post cat sensor, but perhaps a sensor was never there, and I mistakenly read the code location wrong. Would this make sense? If the sensor was never there from the factory, is this a non-california v. every where else emissions type of thing? Trying to make sense of this... Thanks in advance.

 

ill look under my montero and ill see if i can check it out for ya i have a 98 4door fullsize myself...this is not sensor related but there is a wire connectionbehind my head unit that never connected to anything so what it may be too is just a dead wire...not used...ill get back to you