No heat from heater (1989 Reatta)

[carbuff]

The heater stopped putting out heat. I checked the door linkage behind the glove box and the door seems to open and close. I replaced all the vaccum hoses in the engine compartment that I could find and still no heat when set at maximun heat. Any suggestions?

[jchudyk]

If all the vacuum lines are Ok and the trapdoor is working, I would suspect the thermostat. What temp. is indicated on the screen? My '89 runs at about 184 degrees with a 180 degree thermostat. I get plenty of heat (in Minnesota)

[Guest F14CRAZY]

Is your temperature gauge reading that the engine is coming up to full temperature?

Heater core could be plugged as well, but I'm more for your thermostat being stuck open

[padgett]

And did you check the coolant level ? When low one thing that stops working is the heater.

After these, if you have hot coolant (over 140F) and no heat you need to check the hot/cold diverter door which is a rod on top of the HVAC "programmer". You may need to remove the glove box to see. (Sounds like already did).

[Shelby]

Did you check to see if you actually have vacuum to the controller?

I had the hard pastic line that runs from near the brake unit along the firewall to the inside on the car develope a small crack, and was very hard and brittle. It drive me nuts for months till I figured it out.

Check this plastic line for cracks

[Guest F14CRAZY]

Didn't think of the vacuum line...might want to remove the black plastic cover above the passenger footwell and make sure it's still connected (the black one). Mine has come off before.