Most likely the fuel system just needs to be bleed back to the injectors. The number 3 injector could be air locked. To bleed the line, loosen the line at the injector. Then crank the engine over till you see fuel spurting. Then tighten the connection down. If you have a compression release lever, pull the lever so it releases compression on your engine while cranking. Make sure and give the starter time to cool off as well.
If bleeding the line doesn't work, then you will need to remove the line for that cylinder at the injection pump. Make sure to use a back up wrench so you don't loosen the port. Then crank engine over and see if you have fuel spurting from that port.