I'm replacing the O2 sensors (black and blue) due to the dreaded PO137, PO139 and PO420 codes and I don't seem to be 10% smarter than the electric connectors (my boy always did that part and he's overseas right now).

All this time I thought getting the first sensor losened up would be the issue, not this. What's the trick of the green safety clips?

Thanks in advance.

 

Never mind. I wasn't pushing it far in enough by finger, but hte minute I used a pair of needle-nose pliers it came right out.

 

Don't feel bad, I changed out an O2 sensor last week and being fairly inexperienced I had some problems with the electrical connector too. Once I figured out exactly where I had to squeeze it with the pliers it came off pretty easily.