Heater

2001 OLDSMOBILE BRAVADA
111,000 MILES • 6 CYL • 4WD • AUTOMATIC
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CAROLYN NELSON
  • MEMBER
  • 1 POST
Heater goes from hot to cold and then hot again.
Feb 8, 2018 at 10:17 AM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.
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JACOBANDNICKOLAS
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 110,190 POSTS
I need some general information to help. First, is the engine reaching operating temperature and staying there? Are you sure the coolant level is full in both the radiator and overflow? Note: Only open the radiator when the engine is cold. Next, if the engine is warm, coolant is full and there is no heat, feel both heater core hoses under the hood. Under normal conditions, both should be hot. I found a picture online which shows the heater core hoses. They are the two approximately 5/8" hoses which run to the firewall. Check those things and let me know what you find.

Additionally, here is a video from the owner of this site discussing the top ten causes for heater problems. I recommend watching it.

https://www.youtube.com/watch?v=SNRb6pSwYuU
Feb 8, 2018 at 6:30 PM
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