Cadillac Repair: 1991 4.9 sedan deville, minimal heat, heater core

Question
i am getting minimal heat inside car-replace thermostat-
i notice that a/c compressor turns on and off even when
i have temp control set at high temp

thanks

Answer
Could be:

Restriction in heater core.
Faulty AC/Heater programmer.

Check the bottom heater core hose as it should be EXTREMLY HOT and the upper a little cooler is it ?.

try flusihing out the heater core.


Remove the glove box liner and look upwards to the left and you will see a metal threaded rod , Set your controls on FULL HEAT 90 degrees and watch this metal rod it should come towards you and after 2 minutes it should stop moving. Make a mark on the rod with a marker where it snaps into the plastic clip and unsnap the rod and pull the rod towards you and see if you now get full heat. Re-install the rod back in the clip EXACTLY where you marked it.


Let me know