Heater blowing cold air but vehicle is overheating anti freeze is at right level

2001 over heating no hot air from heater antifreeze level is good all belts working

Head gasket. My humble hunch, anyway.

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When the engine is cold, remove the pressure cap from the coolant reservoir.

Start the engine, and as it idles, watch the coolant in the reservoir.

If bubbles start form in the coolant,it indicates a blown head gasket.


your over heating can be caused by a stuck thermostat, fan not working, head gasket problem, or system not holding pressure.
if you are over heating then you lost antifreeze. and you probably have air in your system that needs to be bled out. plus, the original reason it is overheating needs to be fixed if you have not already done so.


The heater is generally the highest point so if you have no or low coolant you will get no heat and over heating. If you have a head gasket leak, a bubble will form blocking the flow of coolant. See above.

Good idea. An air bubble can form in the heater even if there is no head gasket problem as well. The symptom for that is little to no heat even tho engine is at proper operating temperature. If there’s an air bubble in the heater core, there could be an air bubble in the main coolant flow path too , which would cause overheating. If no indications of head gasket issues, suggest to ask shop to air-bleed the cooling system. This job can prove to be very difficult to get all the air out, especially in low-slung sports cars, just b/c of how the coolant path is routed. So if your car is of that variety, make sure the shop follows the manufacturers coolant air bleed procedure to the letter.

A Mazda Tribute is a Ford Escape with different badges, so lots of local mechanics should be able to help you. My first thought is a stuck thermostat. If you can’t recall when the thermostat was changed, it’s probably time. Have a mechanic do it if you don’t know how, and stress that the brilliant minds on Car Talk thought they should take special care to make certain there are no air bubbles in the system when it’s refilled after the thermostat is replaced. The cost is mostly labor so I’d just have them put in a new one without really doing anything to test the old one.

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On some cars it’s important to have the heater control set on Hot when trying to expel air from the cooling system. That opens the valve between the engine and the heater core (if present) all the way.

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Do you know which engine is in your car?