03 dodge wont start please help
 

Well i just bought an 03 dodge and it has been starting right up the last 2 weeks but i went to jump in it yesterday and run to work in them morning and all it did was turn over and over. i didnt know what to do so i just shot a bit of starting fluid in and it started right up and never had a problem the rest of the day. i just went outside to try and start it this morning and no start. i dont want to start it again with starting fluid and get it addicted to it. i replaced the fuel filter yesterday and i thought that'd solve the problem. it is throwing 2 codes and i'm not sure if they are the problem on of the codes came from where i hooked the edge juice up with attitude that came with it and it started sputtering soon after so i took it off. the codes are
P2146-Fuel Injector Group A Supply Voltage Circuit Open
P0341-Camshaft Position Sensor Circuit Range/Performance.
i dont know if this is an electrical problem or a fuel problem and i dont want to tear into it until i get some advice. Thank ya'll in advance.


also idles about 1100 sometimes for no reason and it takes a bit to come down when i shift gears. actually is getting a mile to the gallon better fuel mileage since this happened.