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Equinox smell antifreeze in car, blows cold air when not moving

2008 Equinox blows cold air when not moving. Also has an antifreeze smell inside car. Is it the heater core plugged?

The heater core may have a leak if you smell antifreeze.

And if that’s the case, there’s probably air in the cooling system now that gathers in the heater core causing no heat.

Does the cooling system have Dexcool in it?

Tester

what is coolant level in tank?

Yes the antifreeze level is full. It only blows cold air if I’m not moving. There is no wet spot on the passenger floor.

Is the antifreeze full in the radiator, not the recovery tank? If there is any leak in the system, the coolant will not be drawn from the recovery tank into the radiator when the car cools. Intermittent no heat is a classic low coolant system symptom.

I wondered about that and no I haven’t checked the radiator…but I will. We are having a blizzard so not inclined to go outside today. Wouldn’t low coolant in radiator cause it to blow cold air all the time? As soon as I drive and continue to drive, I have hot air.

No.

If there’s air in the cooling system, and sit and idle, the water pump slows down to a point where the air accumulates in the heater core because it’s the highest point in the cooling system, and there’s no heat.

But when you start to drive, the engine RPM’s are faster, which in turn spins the water pump faster which is now able to deliver a higher volume of coolant thru the heater core, which forces the air out of the heater core, and you get heat.

Tester

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Thank you for the detailed explanation. I’m a 64 yr old lady and I like to know how the mechanics work on all sorts of things. What do I need to do?

You need bring it to a mechanic so they can pressure test the cooling system to see if there are any leaks. And if there are, repair the leaks.

Then the mechanic will refill the cooling system, and purge any air out of the cooling system.

Tester

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Perfect…now I can tell my mechanic what to do. I thought the heater core needed to be flushed. Should I have this done also? Or is it not needed if they find a leak?

No , you do not tell the mechanic what to do. You describe the problem or problems as best and as clear as you can and let him do his job.

As the engine warms up the coo;ant expands, that is why you have a recovery tank in the first place. The additional volume of coolant pushes the air out of the heater core and the heat works.

If you let the leak continue, the coolant level will drop more and the heat will stop working and the engine will overheat but you won’t know it by your temp gauge (if you have one) because the level will have dropped below the temp. sending unit.

Then you will either blow a radiator hose, radiator or head gasket or seize the engine.

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Unlikely on a 10 year old vehicle. If there’s a coolant leak inside the passenger compartment, I’d guess it was where one of the hoses connects to the heater core, not the heater core itself. The symptom indeed does sound like the cooling system coolant level is low. That must be checked at the radiator itself, not the overflow bottle. If it is low then pressure testing the cooling system is a good next step. But let the shop suggest this, not you. You want the shop to be responsible for the outcome of all symptoms cured, not simply that they did what you told them.

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I took my 2008 Equinox in to my mechanic. They said it was low on antifreeze so they filled it. They preasure tested it and found no leak. So I still have no heat when I’m idling. The radiator is sealed and the only way to add antifreeze is through the reservoir. I’ve already paid them $190.00 and it’s still not fixed. What do I do?

you said coolant level was good. they said it was low. how low? you told them you had no heat. they told you the heat output was good? disconnect here? you went there for no heat and they let you leave without agreeing you now had heat?

I was told by the mechanic to check the level in the radiator to see if it went down after I picked it up because I told them that it was still cold air while idling. I find out that my radiator is sealed and no way to check that level. I have a feeling that whoever worked on my vehicle didn’t understand or didn’t care that the real problem was cold air at idling. It was and has been very hot air while driving. I am bringing it back to them tomorrow. Does this answer your questions?

i have an 06 equinox and i did the headgaskets last summer so i have some recent experience with the cooling system. my heater is ok at idle and while driving. your heat is fine on the highway but you stop and let motor idle and it will get cold? i would say my temp gauge sits at about 11oclock and never moves up or down after i am driving awhile. i can turn temp dial from hot-cold and i can hear a slight buzz sound in dash as the blend door opens/closes. i assume yours does the same?

I have started it to warm it up and hadn’t driven it and let it run on defrost to defrost the windsheild. After 10 minutes I open the door and ice cold still and windshield didn’t defrost. Then when I drive it gradually gets warm air from the vents. Also the smell of antifreeze gets strong after it warms up while driving. Every time I stop for a stop sign cold air blows out. Doesn’t matter what dial setting. The red/blue dial is always on warm