I have no heat in my 2000 chevrolet Z71 p/u, even after changing thermostat. When I turn temp indicator dial ther is no change in air coming out of vents.

If there is cold air coming out the heater than there is air in the system. After you replaced the thermostat did you run the engine at idle with the radiator cap off until the engine came up to operating temp? Doing this will purge the air from the system.

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Change the thermostat and start from there.

i would change the thermostat and coolant temperature sensor, this sensor tells the fans when to come on and turn off, hope this helps

I would check for voltage and ground at the fan.Even with a thermostat stuck open you will build up enough heat sitting still to turn fans on. they should come on when the ac is on.Try swapping fan relay with something else and see if they work.

check the coolant level first! and change the thermostat if need be. sit in car until the temp. guage reads normal temp. if it is normal, and still no good heat. it is possibly the thermostat thats sticking. when changing coolant remember to bleed air from system while putting fluid in. it may also need a good flush. good-luck !! i live here in ny and today the wind chill is 8 below zero.

TRY: TURN ON HEATER CONTROL TO PURGE AIR FROM HEATER CORE

change your thermostat.

If this Buick has a 3.8L, there are air bleed valves that must be opened to ensure the cooling system does not develop an air lock. (Wich would cause a no heat condition). If the thermostat is functioning properly you may want to check if there is flow through the heater core. Check by feeling each heater hose at the firewall with engine at opperating temp. They should both be hot and close in temp. A noticable temp difference in the two hoses would most likely be a flow problem, either from an air lock, bad t-stat or plugged heater core. Good luck.

ther are two small tubes that open and close the valve to let in the hot air' one is from right under the carb intake and goes to the right (looking at the engine) right behind the fuse box. if there's o hole in that tube the heat will not work. just change mine becase the tube dry-rotted

why would the heat on a 2000 Chevy Trailblazer only produce heat when the temp dail is to the right to the red indicator, but produces cold air when the temp indicator is any where else on the dial. Thank
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