i would start with the tail light gaskets first its the most common spot and pretty simple to fix...

 

yes the neon is a great lil race car but the neon was more designed to be a cheap lil econo car which it also exels at... i drive my car daily and yeah its a blast to drive with the wonderful 7200 rpm redline of the dohc... but when i drive decent like i do most of the time i've been pulling anywhere from 36-38mpg... pretty damn decent i think...

 

OMG im so happy i found this feed, I have had my '02 neon for a little over 6 months now and i couldnt figure out how the trunk was leaking!!! it leaked so bad it was pooling into the floor, not sure if thats a totally different leak but it only gets wet on the passenger side backseat floor, but i wasnt going to put any sounds in the car until i figured out this leak! worst is when it gets hot out and it looks like a steaming sauna is inside waiting for me to roll my windows down ha ha