no heater again and slight overheating?

2006 CHEVROLET EQUINOX

180,000 MILES • 3.4L • 6 CYL • 2WD • AUTOMATIC

HANNAH WILSON

MEMBER
1 POST

New water pump. then lost heat so bled the coolant system, had some air bubbles. The heat was back then gone again decided to get new thermostat had heat for a few weeks then lost the heat. Bled the coolant system again, got pressure back, had some air bubbles again and had heat for about two weeks. Now no heat again and slight overheating. What could be the issue? Heater core? The hoses are both hot.

Mar 5, 2023 at 7:32 PM

STRAILER

✓ASE Certified Mechanic
54,832 POSTS

So, what happens is the head gasket can leak slightly which fills the heater core with exhaust gases which causes the heater not to work. This guide can confirm the issue, if the test comes up negative, I would try switching out the temperature control blend door actuator which I have included instructions be in the images below.

https://www.2carpros.com/articles/head-gasket-blown-test

This guide can help as well:

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

Check out the images (below). Please let us know what you find.

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Mar 6, 2023 at 11:00 AM

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