Can anyone help me out with the proper way to connect all of the vacuum hoses for the A/C - Heat - Defrost system?

When I bought the car the heater core was bad and they had everything blocked off under the hood. The A/C system still has a bit of a charge in it but the dash control does not operate it properly. I currently have the dash out as we are doing a complete interior so now is the time to try and sort it all out. 

I'm sure we can pick our way through it slowly but I'm also sure there are some talented people on this site that have pics or know there way around this craziness pretty well both behind the dash and under the hood.

Any help is greatly appreciated!!

Many Thanks,

Ken Stout

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I would do all the possible reading you can about the comfort control system on this site 

It is very complicated with a good number of parts 

Russ on our site sells  a book that many like to explain the workings of the system and trouble shooting it 

The service manual is not the best as they upgraded the system in service bulletins over the year 

To be sure your engine does not have vacuum issues —I would block off the hose just behind the carb that goes into the firewall and cabin  about 1/2 inch first 

That will help the engine perform better until you work thru the vacuum leaks in the cabin you have now that are effecting your engine manifold pressures negatively 

Enjoy the journey 

Thanks for the info!! Does Russ have a user name or can I do a search somehow on this site for him?

Russ is Caddy Shack in the — Part Suppliers -  located in the Header on the home page 



Many thanks!! I'm sure this will save us a ton of money in beer we would've had to drive to sort out the issues HaHa


Cheers !!! 




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