electrical or fuel related?

hello i have a 1998 dodge stratus es v6 and am having starting problems when i let it sit for a few days at a time. once it does start it will run good for a mile or 2 then start to miss and almost die until it seems like it dries out. i do notice this is more of a problem when it's damp or has rained outside, car sits outside because bike is inside :-) could this be a bad plug wire or cap or rotor ? what about the fuel pump, don't they usually work or not? i sprayed the cap and the 3 plug wires i can get at,the other three are buried, with silicon spray but this did nothing. i took it to garage abd they changed the fuel filter for me and poured water on wires i guess and couldn't get it to act up because it was initially dry. there are no codes showing up either. thanks for any input or advice. Randy