I just bought an '03 Neon SE and when I go to start it, it won't hold an idle. I have to keep giving it gas so that it will not die. If I give it gas until it gets up to temp, then it will hold the idle and run...but kinda rough. What could this be? I'm going to change the plugs and wires to see if that helps... but what if it doesn't? Any suggestions would be greatly appreciated.

 

most likely a Idle Air Control valve or IAC for short, located on the throttle assembly. 2 Torx screws hold it in place. Should be available at your local auto parts store.