Why is my dodge caravan overheating?

Question

Hi my van begins to overheat when I drive. It's weird because the heating gage goes up to super hot and than drops back down and then goes back up to super hot and then down and then up I'm sure you get the idea but so far it hasnt quit overheated. I have coolent in it does anyone know what could be wrong?

Answer 1

Did you change the thermostat? Make sure you don't have any open leaks if its a closed system. Radiator cap, overflow tank cap, leaking hoses, etc. If all looks good after that but still over heating you probably have a head gasket problem. You can also check your radiator hoses if they are old to make sure they aren't collapsing under pressure.

Answer 2

Lets see, the gauge gies up and down,
If gauge or sending unit were bad the gauge would stay in one place. If the sending unit was not sending the gauge would not react. So eliminate that problem.
If there was a loose connection it could cause this action, but it seems too consistant for a bad connection.
If the thermostat had been changed, ( we don't have that answer)
and installed backward, it would cause these symptoms.
One other problem I once observed was an air lock in the rear of the engine. I don't know what year your vehicle is, or where your sending unit is, but if it is at the rear under the distributor remove it and make sure coolant flows from the opening.
This can happen if the system has been low and allowed air to enter.
Diagnostics are better than maybe its a ????????????
Anyway give it a try

Answer 3

it is unusual that a thermostat would work sometimes...but this does sound like your thermostat is bad...perhaps when it gets so hot the thermostat finally opens up.

Does this occur when you are idling then the gage goes back down once you get on the road? If so I would have the catalyctic converter looked at as this how they act when they are starting to clog up.

Hope this helps.

Answer 4

you say the guage goes up and down which sounds like the gauge or the sending unit is bad ( the sending unit is cheap and easy to replace), but do you see any steam coming from the radiator? thats the important thing, because if your engine is overheating , you need to take it to a mechanic, like yesterday! any day now you will blow your engine

Answer 5

could be a problem with your thermostat or your gage. . . if the gage is just registering hot without the coolant heating up or the car smelling hot then your gage is broken, if that isn't the problem check to see if your thermostat is stuck open, if so you may have to replace it.