Hi Tina, your car may be running hot because of a malfunctioning heater core. Dont freak out yet. It may be something much cheaper to fix. Like maybe the coolant is worn out or incorrectly mixed, maybe the wrong type. Its probably the thermostat which i have had to fix several times over the years. Possibly the water pump as well. Have you checked the belt on the water pump to see if its spinning?
Check the fan too to make sure its not wobbling or spinning after the engine stops. Once the car is completely cooled off remove the radiator cap and start the engine. Look into the radiator and make sure the coolant is flowing. If its not then its most likely the thermostat. If it is flowing replace the cap and check the heater core by running the car until at normal temp. If one of the two hoses going into it is much cooler than the other than its probably malfunctioned. The core is usually on the firewall behind the engine. Let me know if that works.
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