My 95 tahoe just blows cold air. It doesn't matter if the knob is on hot or cold. The heater core is getting hot, it appears as if the door to let heat out of the heater core box is not opening. Is this vacuum operated? I'm afraid I'm going to have to remove the whole heater box.

Thanks,

Don

try your thermostat. It may be froze open. How is the fluid?

Yes I did replace the thermostat. The heater core is getting hot.

Don: Not sure when they changed from vacuum to electrical. My '98 Sub is electrical. I'm pretty sure yours is too. Slide controls were vacuum and dial controls were elec. How about your vent, defrost, floor, etc do they work ok? The temp door motor on my Sub is located behind the glove box (need to take it out) to the left and has a wire harness going to it. You can take the motor out, it's kind of square v shaped, and see if the door is free moving. Again, this is how my '98 works. Hope this helps........Steve

Thanks Stickman,

The vents do work properly, I will try to remove the motor this weekend.

Thanks again,

Don

Thanks Steve,

The motor fixed it. I found it online for 25.00.

Thanks again,
Donnymo

Good job Don and thanks for posting back.