Question about 1999 Chevrolet Blazer

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1999 blazer 4x4 lacking heat during cold days

Our 1999 blazer 4x4 (loaded) will produce good heat when outside temp is running about 45/50 degree but, when its real cold outside (10 to 20 degrees), the vehicle will not produce good heat, not enough to keep you warm in the vehicle. Thinking its a thermastat? Need some help.

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  • Todd Oct 05, 2009

    it was the thermostat. Changed it out (easy job) and we now have good heat.



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Do you have the red fluid or the green fluid in the radiator if you have the red get that junk out of there flush the radiator i had this problem in 98 The dealer said it was ok to put the green back in but i would check the thermostat first

Posted on Oct 04, 2009

Testimonial: "thx! it was the thermostat. changed the thermostat and took care of the problem."

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T-stat may be stuck open or may have been removed by previous owner

Posted on Oct 04, 2009

Testimonial: "thx so much. Changed the thermostat and everything is back, got go heat now."


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