Ok, I have a 96 coupe with a 2.2 liter. So my car starts over heating, so my dad replaced the theromostat in it. Well the temp only goes up if I have it in neutral for 5 min or longer, and my low coolent light constantly stays on since we put the new thermostat in it. Nothing is leaking, and all the fluids are full. When I'm driving it the temp guage is fine no problems...any ideas?

When it overheats at idle, check if the cooling fan is coming on.

thermastats are bad right out of the box!
Id purchase a new one and go from there?........Marc

add more coolant

holy crap ,old post here guys. Bet the problem was solved a couple of years ago ..............lol