Yesterday I replaced the radiator in the LSE. It started leaking pretty good on the way home from work one night about two weeks ago, check engine light and temp light came on right as I got into my driveway so it did overheat. I got everything hooked back up, added coolant/distilled water, let it run until it was warm and the thermostat opened, then topped it up. I went to take it for a drive to check things out, about a mile from home the temp gauge dropped all the way, it's also not building any pressure in the system. No leaks that I can detect, not sure exactly what is going on here. I'm thinking the thermostat may be stuck open from getting too hot, but I'm not sure that would cause the lack of pressure in the system.