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Q: My car is running hot and air not working.

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My car is running hot and my heat not working. I just changed my heater core and put in a fail safe thermostat. I'm not sure what the issue is. I feel pressure on my hoses. So I'm sure my water pump is working.

Hi there - I suspect you have both a malfunction thermostat (still), or clogged cooling system which is causing the overheating issue. The lack of heater function could have 5 causes: the engine is not getting up to correct temperature (center of the gauge) due to a malfunctioning thermostat, the heater control valve is not letting hot coolant into the heater core, there is a restriction in the heater system that is preventing adequate hot coolant flow through the heater core, the heater fan is not working to transfer heat from the heater core to warm air for the passenger compartment, or the air blend doors inside the heater are not working properly to route warm air to the desired vents. I would recommend a heater system inspection](https://www.yourmechanic.com/services/heater-is-not-working-inspection) by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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