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Idle over heat fixed by AC?

I got 2005 Malibu 3.5L v6 and when my AC is off the temp goes from 50% to 65% close to red zone which is 75% and above but the thing is when I turn on the AC it is like problem doesnt exist also when AC is off and it is overheated around 65% if I start driving around the temp goes back to normal. I checked the fans they work even when AC is off. Water pump and thermostat replaced coolant flushed 20k miles ago about a year or a year and a half ago with serpentine belt replacement.

Please help me out guys.

If its not going into the red zone, it should be fine.The radiator fan should turn on to cool the engine when it reaches a certain temperature.Do you have unusual hot weather recently?

Sounds like the radiator fan isn’t coming on and when the A/C is on the condensor fan pulls enough air through the radiator that it helps cool the engine down

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fans? you have 2? side by side? i changed the coolant on my 06 equinox and had the chance to see the fan come on while idling and using the bleed valve. i dont usually sit in the driveway and listen for the fans on/off so i assume they rarely run. i have never heard them running in the garage after i get home. and the equinox is known for somewhat odd behavior. electrical and such.