Driving the last few days at 100 degrees and today its not hot and the thing overheated, with what sounds like a leak.

Theres coolant behind the the thermostat housing under the intake. I have a 1999 v6 Galant. Thermostat was changed a few months back changed upper radiator hose, bottom seems fine. any suggestions on why it sounds like its leaking from under the intake? left car by side of road, going back after work to try and resolve the issue.