I spent entirely way too much time trying to get one of these style extruders on my Ender 3. Maybe I picked a knock off without realizing it, maybe mine was just defective, I'm not entirely sure.
But it was ultimately the cause for my printer underextruding on certain layers. If you need a new extruder, go for something better than these cheap $20 ones and get an actually decent one.
But on the bright side, my printer is finally fixed! It feels nice to be able to get back into the hobby again.
Neat! I use one of the metal Creality extruders, which seems to work fine, but maybe this is the next step in my quest to nail my extrusion...