Iwata neo airbrush

[jpw]

Hello hoping for some help I have a iwata airbrush for a little while now and never really had a lot of consistancy from it, a appreciate paint thickness has a lot to do with successful airbrushing, but every time I use it there seems to another issues. I am getting Back pressure into the paint cup now .I have already replaced the nozzle, and when airbrushing I am getting a lot of splatter. any help I would much appreciate should I be looking for another brush or replace parts on this thanks John