So I was replacing my downstream O2 sensor today on my 1999 Honda Civic EX. It's a d16y7 with a y8 head. So I bought a Denso O2 replacement for a y8, and it seems as if the fitting clip on the new O2 sensor is the same size as the one on the harness. Y7 harness maby???? Idk. I'm still learning, so dont mind my stupidity.