Im driving home from the dealer and the car starts to overheat! I look over at the autometer, and its at 250*! So i shut it down and looked over the motor, there was plenty of coolant, so my dad told me the thermostat probably got stuck so i whacked it with a small hammer, and it started to cool off slowly as i drove. So then im looking at the reciept from Ford and it says i have a nail in my tire and theres a slow leak...but they didnt tell me, and they didnt offer to fix it at the dealer. So i go to firestone, get the nail out, and then i go to leave and i thought well maybe the cooling fans just arent working. But i checked, and they were turning on at 212* like they should. Well i drive back to my friends house where im staying, and shut it off. Go inside and eat and my dad calls. He tells me to drive it around the block a few times and see if the fan keeps cycling like it should. Well it does for about 10 minutes...they come on at 212, it goes to like 215ish, then it comes back down to 210, and keeps doing that. Then after about 10 minutes, it just started climbing to 245 where i shut it down. Any ideas here?