No heat


Asked by Jan 23, 2016 at 08:10 AM about the 1999 GMC Sierra 1500 SLT 4WD Extended Cab SB

Question type: Maintenance & Repair

Hvac works, but no heat is generated. Any thoughts?

2 Answers


Low on anti freeze, thermostat needs to be replaced, radiator fan not working, blend door is not switching over from A.C to heat, this is just a few things but a little bit more information on what is going on would be helpful to diagnosis better.


Also in front of the engine where the grille is you may have a bad inter cooler. Best thing would be to put a piece of cardboard behind the the grille so the the engine doesn't blow cold air into your cat

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