1997 Pontiac Trans Am Heater

1997 PONTIAC TRANS AM
105,000 MILES • 5.7L • V8 • RWD • AUTOMATIC
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JAMESWHITE
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I was not getting any heat so I changed the thermostat and filled the fluid until both bleeder bled and caped it off. it will get warm at a idle but the temp gauge stays at 168-175 when moving But my wife said that is normal and she had good heat last year. I can work on it but I am a Ford guy don't know anything about it and don't want to mess it up. it is a show quality car
Nov 16, 2014 at 3:09 AM
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WRENCHTECH
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168 to 175 is not normal if your readings are correct. This engine uses a 195 thermostat and the cooling fans don't come on until about 225 so the first thing you need to do is verify the temp using a laser thermometer.
Someone may have incorrectly removed the thermostat at one time.
Nov 16, 2014 at 4:09 AM
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JAMESWHITE
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OK thanks I will get a 195 thermostat I don't think there is a way to put it in wrong it wont fit upside down right the housing wont fit.I hope the guy at thr auto supply just gave me the wrong one, I just told him what car I had, Is there any think else it could be? Is there a vacuum switch that turns the heat and a/c back and forth like a Ford. Thanks again
Nov 16, 2014 at 4:26 AM
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WRENCHTECH
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With the engine at full operating temp, locate the 2 heater hoses where they go into the firewall and feel them to see if they are both hot to the touch. If not, the issue is in the engine. If they are both hot, the heat in that vehicle is controlled by a blend door that regulates heated air flow. it is operated by an electric motor/actuator. The problem can be that the actuator is stripped or inoperative or the door itself could be damaged. This is what needs to be determined by examining the actuator and see if it is responding to heat change commands or not.

Nov 16, 2014 at 4:29 AM
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JAMESWHITE
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Thanks I will check
Nov 16, 2014 at 4:36 AM
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JAMESWHITE
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Hi I checked the hoses and one is warm and the other is cold. What do I do now. Did the auto parts guy give me a 165 temp thermostat I am calling them now to get a what 195 or 210 temp. Thanks
Nov 17, 2014 at 8:24 AM
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WRENCHTECH
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Verify the engine temp first. If the engine is actually getting hot, you may have a restricted heater core.
Nov 17, 2014 at 11:08 AM
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JAMESWHITE
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will a back flush help I am taking it in this morning Thanks
Nov 18, 2014 at 3:29 AM
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WRENCHTECH
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That's an indication that the heater core is plugged up. Someone may have added sealer to the system at one time or left Dexcool in there for too long,

I would remove the 2 heater hoses and use a garden hose to flush the core in both directions and see if that helps.

Also make sure you have sufficient coolant and the core didn't just freeze.
Nov 18, 2014 at 3:40 AM
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JAMESWHITE
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Ok thanks
Nov 18, 2014 at 3:44 AM