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Q: My car is over heating while sitting at lights, fluids have been checked and are OK.

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My car is overheating at lights or driving slow. My fluids are OK.

My car has 200000 miles.
My car has an automatic transmission.

A: This is a classic sign of a radiator fan th...

This is a classic sign of a radiator fan that is not working. When your car is moving, air is being forced through the radiator and cooling your coolant. At slow enough speeds, the air flow is not enough. There are number of factors that affect the necessary speed to force enough air through the radiator to cool your motor. That detail is not usually necessary to know because of the radiator cooling fan.

It is possible there is a coolant flow issue as your car has many miles on it. If the coolant is dirty, you will want to consider this. Before considering coolant flow issues, you can run your car sitting still until the motor begins to run hot. Be sure to monitor it while you do this. Leaving it unattended is not advisable. When the temperature gauge begins to show hotter than normal, the radiator cooling fan should turn on. If it doesn’t, this is your problem. Testing why it won’t turn on should begin at the cooling fan relay. To do this, you will need a wiring diagram and a test light. Experience is helpful as well.

If you should need further assistance with this, a certified technician from YourMechanic can come to your location to perform these checks and properly diagnose your overheating issue.

Good luck!

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