Q: Thermostat leaking coolant

asked by on February 25, 2016

I need the thermostat in my car replaced as it is leaking coolant. When I turn on the heat or AC, it blows a cloud of misty grey smoke. The car leaks coolant even when idling.

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Hello, the coolant leak will need to be repaired sooner rather than later to avoid overheating and engine damage. I would say that you have a leaking heater core based on a coolant leak and a mist from the vents. The new thermostat is probably not an issue, but the coolant leaks will still need to be repaired. Have a mechanic from YourMechanic come out and pressure test the cooling system to detect the leak and make the proper repair. If the heater core is leaking there is a chance that the instrument panel must be removed for access to the heater box.

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