What's causing my car to over heat?

I have a 02 Ford Focus. EVERYTIME we drive it the dang thing overheats and when it starts to go off of course the air blows hot. However the thermostat will go back down and the cool air will come back on again SOMETIMES white driving. I can also shut car right off sometimes and start it back up a few mins later and its fine, It just goes up and down on its own. All the right amount of new fluids and all that are in the car. We had a new fan put in also and its still not helping.

It goes all the way into the red! And it doesn't ever take long after being in the car. And when its in the red is when the air goes to warm air.

What do you mean by overheats? Is the gauge going into the red zone or staying just below it.

The gauge will go up and down depending on if you are in slow moving traffic or cruising down a clear road.
If hot air is only blowing out the vents when the temperature is high that could be a sign of an air block in the heater box.

What's causing my car to over heat?
I have a 02 Ford Focus. EVERYTIME we drive it the dang thing overheats and when it starts to go off of course the air blows hot. However the thermostat will go back down and the cool air will come back on again SOMETIMES white driving. I can also shut car right off sometimes and start it back up a few mins later and its fine, It just goes up and down on its own. All the right amount of new fluids and all that are in the car. We had a new fan put in also and its still not helping.

Underneath the upper radiator hose is the thermostat. Either replace it with a higher rated temperature one or remove it permanently.

It sounds like possibly an air pocket in the cooling system which can lead to fluctuating engine temps as the air pocket moves around in the cooling system or gets trapped in a cylinder head or heater core. Even if coolant fluid levels are topped off, you can still have an air pocket which needs to be bled out. Any time the cooling system is low on coolant or opened up for repairs, you can get air into the system which needs to be bled out.

Have a local repair shop or dealer perform a bleeding operation to remove any trapped air and check to make sure the engine cooling fans are coming on when they should (bad temp sensor for fans or fan relay?), the thermostat is OK and working as it should, no blockage in the radiator/flush the cooling system, check for a bad head gasket/pressure test the cooling system, etc…

Video on how to bleed cooling systems in general terms…

Not a car expert. But it sounds like your thermostat is broken.

I had the same problem with my van, it would overheat but never did emergency shut off. But if I were you I'd have it checked out immediately. My van ended up blowing up on me and basically became totaled. So go check that out ok.

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