Q: My car was overheating and when I turned the heater on, it would blow cold air. I just replaced the thermostat and my car is still overheating

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My car was overheating and when I turned the heater on, it would blow cold air. I just replaced the thermostat and my car is still overheating
My car has an automatic transmission.

Hi, thanks for writing in. This is likely due to bad coolant circulation. This can the be the result of several issues. Due to the fact you just replaced the thermostat, the issue may be due to another clog in the system. Start by attempting to solve the simple problems. Flush the radiator and attempt to clear any debris that may be stuck in the system. It is also possible for the heater core to become clogged as well. Water pumps are another source of poor circulation. These can be replaced, but are not serviceable. Keep a very close eye on the level of coolant. If you are loosing coolant, where is it going? Do you see a puddle? Is it being burned in the engine? These observations can help diagnose more serious issues if the first suggestions did not solve the issue. Here at YourMechanic, we can also have a technician come to your home or office to inspect this overheating issue for you, and make or suggest the necessary repairs.

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