I bought 2 upstream sensors from a friend that didn't need them for $10 a piece. Great deal but now I'm looking at them, there are no markings or part numbers on them. He says that they are motorcraft but hell I can't tell. For those of you that have replaced these are they marked with a part number?
Mine have a black wire protector with a black plastic connector.
Thanks

 

Got an O'Reilly's, etc (or as dealer) near you? Can always take it in and compare.

I'm sure they won't mind not selling you one

MGD

 

I have my two downstreams in my toolbox that I can take a look at later today.