1998 Plymouth Neon

Sorry for the late reply.

How hot is it getting in degrees F? Does the radiator fan work? Can you check applicable trouble codes?

Some commonly replaced parts for overheating, thermostat--water pump maybe even serpentine belt.

There is a coolant temp sensor on your vehicle, but, unless there is a code or something that points in that direction, that sensor isn't my first thought. The sensor is located rear of engine close to cam sensor.

I realize this is an old post. You probably don't even own this vehicle anymore. In the future hopefully you won't have any vehicle issues, but, if you do keep the site in mind. The site has more moderators than it used to. It's free.

Have a good day.