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1978 Cad No Heater Air Flow


BIGBIRD2004
01-25-2004, 08:30 AM
I HAVE A 1978 CAD COUPE DEVELL AND I DONT HAVE HEAT COMING OUT. ONLY ONE PLACE HEAT COMES OUT AT AND THAT IS ON MY FLOOR NOT ANY WHERE ELSE CAN ANY ONE HELP ME FIX THIS PROBLEM. I DONT KNOW WHAT TO DO IN THIS CASE. :banghead:
:banghead: :banghead: :banghead:PLEASE HELP ANYONE THAT CAN HELP

michelq
01-25-2004, 08:40 AM
check vacuum hose under hood on carb lead to the programer on right side

BIGBIRD2004
01-25-2004, 08:48 AM
check vacuum hose under hood on carb lead to the programer on right side


A FREIND TOLD ME THAT THERE ARE FLAP THAT ARE NOT OPENING LIKE THEY SHOUD WHEN THE HEAT IS TURN ON.

michelq
01-25-2004, 08:54 AM
all the duct doors vacuum operated except heat door which operated by a/c programer

BIGBIRD2004
01-25-2004, 08:58 AM
Frist What Is A A/c Programer?
Next How Hard Is It Tofix So I Can Get The Heater To Work?

BIGBIRD2004
01-25-2004, 09:11 AM
Is This Problm Fixble Or Not

michelq
01-25-2004, 09:16 AM
did you check the vacuum hoses first . step by step.a/c programer it is controler it is an electric and vacuum operated

pleptuch
06-04-2006, 10:31 AM
Hi there, just joined the forum and thought I'd give my two cents.

I have a 1978 Buick Park Ave, probably somewhat similar system that I just got to work again after years and years and years of not working. I had about $1000 worth of ac work done on it about 7 years ago, including upgrading to a R134 coolant system. After putting in all the expensive stuff, my mechanic said that they could get the controller to work and left it at that.

A few months ago, I found a wrecked 79 buick in a junkyard with an intact ac system and took out the vaccum lines, wiring harness, control module and dash selector panel (or whatever it is called) from the wrecked one and put it in mine. The used parts ran me about $70.

On mine, hot air was blowing in all the time (like 120-130 degrees in the summer). It was stuck in the open position instead of the closed one. There's a flap that opens and closes to the engine compartment that regulates the amount of hot air coming in from the heater box. This is behind the glove compartment on my Buick. There's a horizontal threaded rod that extends from the flap, which connects through a little plastic connector to an upsidedown "L" shaped arm that extends out of the controller. Normally, the L arm rotates and through the contraption, the door opens and shuts. When my controller went bad, as I selected a temperature from the dial on the dash, the controller arm didn't rotate. Once I finally got everything figured out, I took the buick into the shop, added some new refrigerant for $65 bucks and halleluja, the ac works.

Hope that help you or someone else out there.

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