Engine overheating when the A/C is turned on?

Tiny
JOE1953
  • MEMBER
  • 2016 CHEVROLET TAHOE
  • 5.3L
  • V8
  • 2WD
  • AUTOMATIC
  • 198,000 MILES
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?
Saturday, May 24th, 2025 AT 5:45 PM

9 Replies

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,137 POSTS
What happened with this problem?

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

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Sunday, May 25th, 2025 AT 12:55 PM
Tiny
JOE1953
  • MEMBER
  • 793 POSTS
The connected needed cleaning.
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Monday, May 26th, 2025 AT 7:10 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,137 POSTS
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.
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Monday, May 26th, 2025 AT 10:41 AM
Tiny
JOE1953
  • MEMBER
  • 793 POSTS
  • 2016 CHEVROLET TAHOE
  • 5.3L
  • V8
  • 2WD
  • AUTOMATIC
  • 184,000 MILES
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?
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Monday, May 26th, 2025 AT 2:53 PM (Merged)
Tiny
KEN L
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Did you replace the thermostat?
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Tuesday, May 27th, 2025 AT 9:50 AM
Tiny
JOE1953
  • MEMBER
  • 793 POSTS
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?
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Tuesday, May 27th, 2025 AT 4:32 PM
Tiny
KEN L
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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.
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Thursday, May 29th, 2025 AT 10:02 AM
Tiny
JOE1953
  • MEMBER
  • 793 POSTS
I replaced the thermostat and that fix the problem the engine is not overheating anymore.
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Thursday, May 29th, 2025 AT 3:59 PM
Tiny
KEN L
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Glad you could get it fixed, thanks for letting us know. Please use 2CarPros anytime we are here to help.
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Friday, May 30th, 2025 AT 9:49 AM

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