no heat

2004 GMC YUKON
190,000 MILES
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MBERRIOCHOA
  • MEMBER
  • 1 POST
both driver and passenger temperature set to 90 but no heat is blowing.
Jan 3, 2020 at 11:39 AM
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JACOBANDNICKOLAS
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 110,190 POSTS
Hi,

If you lost heat to both at the same time, I suspect the heater core is plugged or you are low on coolant. Also, confirm that the engine is warming up to operating temp. It could be related to a faulty thermostat.

Take a look through this link first and let me know if it helps:


https://www.2carpros.com/articles/car-heater-not-working

If you get the chance, let me know what you find. Also, let me know if both heater core hoses on the firewall (under the hood) are getting hot when the engine is running and the heater is on.

Take care. I'll watch for your reply.

Joe
Jan 3, 2020 at 11:12 PM
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