Ok, i got up this morning and took my kid to my sisters and started to drive to work. got about 5 min and noticed my heater was still blowin cold air. i looked at my temp guage and it was pegging. i shut of the engine and started it right back up and the heater started blowing hot air and the emp guage went down. then at lunch i went to pick him up then i went home let the car sit for half an hour went to drop him off at daycare. on my way back to work i noticed it was pegging again so i turned the heat on and it didnt do anything. so i shut it off again and started it and left the heat on and it started to go down. both upper and lower hoses are hot and have pressure. so that makes me think the thermostat is opening and closing, but i may be wrong, any one plezzze help. the fill jug was empty, and the radiator did have some coolant in it. i have put 3000 miles on it since the rebuild with no problems.