hey i ahve a 95 firebird 3.4 5 speed and my tempeture gauge keeps going way up but if i crank the heat in the car it goes down somewhat but usally not enough to be down by normal temps i know u are thinkging thermostat but i already changed it and its not that still does it. i recently put in a new radiator i think i might have used the wrong antifreeze do you think that would cause this problem i really need tog et it fixed. also my car is for sale needs some work if anyone is intrested email me if you are spartyac@yahoo.com
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Is it losing any coolant?

 

no it seems to be staying full my dad said maybe there isa big air bubble in the system thats keeping the coolant from getting there but i dont know its also kinda rusty in the radiator wen i open the cap so im gonna try flushing the system today but i really have no idea wat the problem could be
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I've heard of the air being in the system will cause it the run hot. You make have the burb the system.

 

yeah, if i were you i would flush it and get that air out of there..
does the temp go down when its on an AC setting, or vent setting (i know you said heat, but is it on AC or vent..?)

 

same problem here !

 

There could be a few reasons. Any green antifreeze would be fine...If you put a new radiator in recently then chances are there's air in the system. Take out the battery then remove the coolant resevoir and flush that out good along with the rest of the coolant system. Bleeding it can be a real pain.