I'm trying to replace an o2 sensor and cannot for the life of me pull the connector apart. I push down on the green spring-loaded thing, hear a click, but no luck pulling the connector apart. Tried every connector I could find in the engine compartment like this and no luck releasing any of them! FSM is no help.

 

push in green tab
place flat head screwdriver at the bottom
pop off

 

Yeah these things stink sometimes pushing the connectors towards each other while squeezing the spring loaded thing will help. Good luck