Q: If the thermostat is bad would it cause the heater core to not work properly?

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I have read online that if the hoses leading to the radiator from the thermostat are cold then that means the thermostat is bad, but would that be the reason why my defrost doesn't work properly? When I start the vehicle I smell what could be antifreeze, just not sure if I should jump to replacing the heater core or hope the thermostat dose the trick.

Hello - you are correct. If the thermostat is stuck open, not allowing the engine to warm up properly, there won’t much, if any, heat in the passenger compartment. However, if you are smelling coolant in the passenger area, chances are the heater core is leaking as well - not a happy occasion. I would recommend a heater inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, confirm this diagnosis, and give you an accurate assessment of damage and cost estimate for repairs.

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