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.

Tester

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.

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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.

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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?

Like stated above it can be a bad thermostat, you could have air trapped in the cooling system and it will have to be properly bled. It can also be a bad fan, a blown or cracked head gasket but before we jump to that buy a $20 head gasket tester on Amazon, it comes with testing fluid, you fill it to the line in tube and it goes into the place of a spark plug and will turn from blue to yellow/green if there is a blown head gasket/cracked block.
But I’m betting this problem has gone on for some time and you didn’t have a big overheating incident that caused multiple overheating events. If it’s been going on a while I’m betting thermostat or air in cooling system.
Any time you do anything with the cooling system, you always replace thermostat, radiator cap and some times it’s good to get a water pump, pulley tensioner and drive belt.
At minimum, replace thermostat, radiator cap, coolant temp sensor and bleed your coolant of all air.
If there is a bleeding screw by the top radiator hose, crack that open while running engine and keep it cracked until it stops bubbling with your heater on full blast and getting to operating temp for at least 15-30 minutes.
You can also buy a no spill coolant bleeding kit. It has a lid and extension tubes and a gasket with radiator cap that seals it to create a high point in the Cooling system that gets all the air bubbles to travel into that huge funnel. You must keep it filled at least halfway up the funnel.
Do a full cooling system flush and bleed and while you are doing that change any swollen hoses and the thermostat. Then if it continues after that get a block/head leak tester kit and follow directions. There are many YouTube videos that can show you simple steps.

In the ‘old days’, I’m guessing thirty or more years ago it was possible, and quite often, to install a replacement thermostat backwards.

I don’t know if that’s still the case, today.

After reading that, I know to NEVER listen to anything you say.

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lol … I’m guessing this is another of our AI bot visitors.

Edit: I’m seeing some other posts from this same visitor which are helpful & informative, don’t seem like bot posts. For some reason this visitor is posting on older threads. @MadeFromMetal1988_182007 , care to explain?

Bot or not he/she/it/them knows where to get the head gasket test kit and where to put it. Still trying to figure that out.

I’ve never heard of screwing somthing into a spark plug hole to do a chemical test for a head gasket leak method, but I suppose .maybe something like that actually does exist. @MadeFromMetal1988_182007 , are you able to post a link to that product? Usually if a head gasket is leaking coolant into a cylinder, you’d just remove all the spark plugs and crank the engine to see which hole the coolant squirted out, no need for anything fancy.

Since (@MadeFromMetal1988_182007) other post didn’t make since for the thread or seemed like someone that has read a lot but has ZERO hands on experience… Like pulling an axle to check the seals, bearings and Hub??? What???

And since he/she/it has not been back to tell us why we are wrong or to go screw ourselves, I am thinking BOT…

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