why is my 03 Sentra surging?

Question

Replaced throttle body and a coil

Answer 1

P0183 is for a Faulty Fuel Temperature Sensor, which is built into the fuel pump assembly if you dont have correct fuel pressure or it is not holding pressure the pump will need to be replaced 

for P0507 you have to do idle air relearn, its easier if you disconnect the battery for an hour or so then do the relearn 

http://nissanhelp.com/diy/sentra/projects/nissan_sentra_idle_air_volume_learning.php