engine overheating when the A/C is turned on?

2016 CHEVROLET TAHOE
198,000 MILES • 5.3L • V8 • 2WD • AUTOMATIC
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JOE1953
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when I turn the A/C on the temperature gauge goes up to 235°F and coolant bubbling in the reservoir and overflowing. How do I fix this problem and what to check?
May 24, 2025 at 5:45 PM
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STRAILER
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What happened with this problem?

https://www.2carpros.com/questions/headlamps-9461371

May 25, 2025 at 12:55 PM
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JOE1953
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the connected needed cleaning.
May 26, 2025 at 7:10 AM
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STRAILER
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If it overheats within the first 15 to 20 minutes of driving, then I would change out the thermostat. Is the cooling system full, does it have a leak? If not and it takes a long time to overheat it can be a blown head gasket. I would go over this guide to help us narrow down the problem and give us more information.

https://www.2carpros.com/articles/engine-overheating-or-running-hot

Please go over this guide and get back to us.
May 26, 2025 at 10:41 AM
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JOE1953
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the temperature gauge go up to 249°F for a few minutes and then drop back down to 228°F and engine cooling fan never cut off and when I turn engine off the engine cooling fan still be running.but I don't hear no boiling over in the radiator or reservoir I replace a new Acdelco engine cooling temperature snesor and waterpump and it still doing the same thing. the gaue go crazy when driving around 70 miles per hour what I need to check next?
May 26, 2025 at 2:53 PM (Merged)
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STRAILER
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Did you replace the thermostat?
May 27, 2025 at 9:50 AM
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JOE1953
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no I didn't replace the thermostat, I take the thermostat out and test it in some 204°F hot water the thermostat didn't open up and I pour some water down the thermostat housing neck no water didn't pass through do that mean the thermostat is bad?
May 27, 2025 at 4:32 PM
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STRAILER
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The thermostat should open at that temperature , I would get a new one and install it. Let me know what happens please.
May 29, 2025 at 10:02 AM
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JOE1953
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I replaced the thermostat and that fix the problem the engine is not overheating anymore.
May 29, 2025 at 3:59 PM
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STRAILER
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Glad you could get it fixed, thanks for letting us know. Please use 2CarPros anytime we are here to help.
May 30, 2025 at 9:49 AM