Hey I ordered an 02 sensor from Advanced Auto using the part number S13 SR20DET REDTOP: 22690-19P20 ('87 280ZX). I found that part number in the SR20DET FAQ thread. Well the one I got has a shorter wire that the one in the car, as well as the threads are a lot smaller. Here is a pic of them both.
Did the auto parts store give me the wrong one?