Ok I did a search first but didnt find the info i was looking for. My car started over heating today. I first noticed the SES light and pulled a code 14 coolant temp sensor hi. Well it was high not because a bad sensor but the coolant was way over heated. The code is only supposed to go off when the sensor reads 304 degrees F which means it was very high. Im sure the sensor calbration is off but it works. My gauge which is on a sepeate temp sensor was pegged. Anyways I shut off the car and noticed the overflow tank was extra high and almost over flowing. I noticed no leaks what so ever. Nothing comeing from the water pump weap hole either. There is no water in my oil. The only coolant I noticed was by a vaccum line connection at the charcoal canister. That vacuum line goes to the intake but the area where I noticed coolant was next to the over flow tank. Although I dont see a trail I think thats where that coolant came from. There is pressure when I pulled open the red lever on my rad cap. Anyways once it cooled off again I noticed the overflow is now empty, it went from full to empty but the rad is still full. I started it up and took the cap off. At first the rad began to actually fill up..... probally because the thermo is closed but once it warmed up it dropped down indicating to me that the thermo is working. So I elimanated an external leak the water pump and the thermostat as well as all the hoses, the timing is fine there has been no work done to it recently and when work is done I do it so I know its nothing incorrrectly done, oh and the fan is working and the rad and heater core are fine. It has never had an over heating problem before today. One wierd thing that has happened in the past was that 2 years ago it was losing coolant and I never found out where, no external leaks and no coolant in the oil or white exhaust. However it stopped and never happened again. Now I think it did lose coolant since the overflow went from full to empty so I am thinking an internal leak. I also noticed that I have white smoke coming from both exhaust pipes. It is cool here 45 F and raining so that could be because of that, it seems like more white smoke than it should be at idle even if its cold and rainy. Well this just started today so it happened just like that which is strange, you would think it would be gradual. Anyways this is a 2.8 V-6 1989 MPFI engine with 127,500 miles. Can you have an internal leak without it clouding up your oil? Especally since it just started happening today? I am thinking head gasket or crack or warped heads or block. Is there a way to tell this or the difference between a blown gasket and a crack or warp in the head or block with out tearing it all apart?Also on the 2.8 can an intake gasket cause this? I dont know if the intake gasket on this motor holds back coolant or not, not sure on this motor. How about something wrong with the throttle body since I noticed that it has a coolant line going to it. Oh yeah and I do have a full air dam thats not broken. Thanks for any help you guys can give ~ Erik

 

Can anybody help?

 

Oh never mind I took out the thermostat and wired the fan to run as soon as you turn on the ignition and its fine now. It runs at 140. So I guess it was the thermo after all. It was sticking closed sometimes and other times opening, I guess that why I saw flow in the radiator when I checked. Weird cuz it seemed to open and close fine when i pulled it out and moved it with my fingers. Oh well guess i will get a new one when I get the chance