QuestionI have a 1992 Cadillac Deville 2dr. My problem is wuth the heater.
I have a digital push button type heater. Once the engine warms up I push the button for heat and it will blow warm air for about 5 minutes then the air blows cool to cold.
I have had a new thermostat put in and checked and it is okay. Any idea of what's the problem...thanks....
Bob in Cincinnati.
AnswerFirst check your heater hoses where they go thru the firewall into the dash. One should be HOT and the other slightly cooler.
Next, remove the glove box liner and locate a small threaded metal rod which opens and closes your damper door.
Put the system on full heat and watch the rod as it should travel towards you and stop. When it stops COMPLETLY after 3 minutes unsnap the rod from the plastic connector and see if you can pull the rod any closer to you. If you CAN and you get heat, the programmer of which the snap that is connected to the PLASTIC arm is faulty.
If you CANNOT move the arm any closer towards you, put it back in EXACTLY the same position.
Watch the metal threaded rod as you turn the system to full AC and the metal arm should travel away from you about 4 inches or so.
If the metal arm cannot be moved towards you anymore when you are on fullheat and it DOES travel away from you approx 4 inches when on AC the programmer is OK and your problem is most likely a restricted heater core that will have to be replaced.
