I would like to reposition some pot lights - before drywalling the ceiling. They have been wired using push-in wire connectors. How do you release the wires from a push-in wire connector ??
If you're talking about an outlet - or a similar concept fixture - the best tool I've found is a flat head jeweler/precision screw driver.
The wire is being held in by this:
You can see you'll need to push that "tab" away from the wire, from the back of the outlet you should see a small rectangle hole next to each circular hole that the wires are in:
MAKE SURE POWER/BREAKER IS OFF YOU WILL BE TOUCHING A "LIVE" WIRE Insert a small jeweler screwdriver in the rectangular hole/slot, use the box as your pivot point and the screwdriver as your level (bring back end of screwdriver towards wire to force "tab" away) and gently pull the wire out.
* If the outlet is old/weak or the wire wasn't inserted in deep you can sometimes get away with just twisting the wire back and forth while pulling.
I am guessing you are talking about something like what Halo has seen in the image below.
To get these out you are supposed to just twist like hell and pull out. I have had to pull a couple out in my basement and it takes a minute. Also wear gloves because there are a lot of sharp edges around.
If you are going to rewire you may need to install a new connector. Sometimes when pull these out you ruin the strapping. Make sure if you reuse that it grips firmly.