Heat blows COLD, like cold air from outside cold. All speeds work and A/C does work. Im not low on coolant, and thermostat is less then a year old. Car maintains temperature normal. Both fans work when supposed to. Ive checked the heating lines and such nothing strange about them. Anyone have any ideas?

Also this is a 1992 Z28/5.7

Thanks, Steve

 

Is it leaking any coolant inside, could be the heater core?

 

maybe the vacuum operated door that moves when you turn the lever to hot isn't working?

 

Heater core is fine and its not leaking coolant anywere in or out of the car. Ive gone through all the different controls and all the air moves in every position. Only thing is that the air is just cold lol.

Oh sorry misread what you said about the temp lever...im gonna go drive around and see if the outdoor temp changes the air coming out. Ill try A/C and what not.
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Oh wow thats really strange...just got in the car to leave...and i have heat...

Thats really wierd, it hadent been working for the past week or so. It hasent been that cold luckily so i havent needed the heat. I guess something just got stuck...but i dont know what.

I feel dumb asking about my car that just fixed itself...

 

GREMLINS

 

lol what he said.

 

even though you say you changed it a year ago, i would double check your t-stat. My dads van had the same problem and it was the t-stat. just my

 

I agree on the sticking heater valve. Stuck one moment, unstuck another....

If the engine temp is normal, the thermostat is probably working fine.