Depends on your router, distance between router and printer, driver settings. There are lots of factors that can be part of that problem. Try to connect printer directly to PC wait for driver to install and print some documents. After that - repeat print same document - through wi-fi. That way you cut off driver setting.
All the rest - can be caused by your network. But I'm thinking - that your printer is stuck in calibration longer then usual before prints comes out. And that can be part of your problem as well.