Please Help, Bad heater core?

[00 Ragtop Z]

as so ably pointed out, the heater is on teh vacuum system for control. Just ahd work done--KNOW that's teh case!

[Rob B (shoebox)]

Originally posted by CLWILSON
It appears looking at the control module that the cable opens the door allow the air to flow over the heater control, but there is a vacuum line on the heat control as well that must control the vacuum driven heater valve that is under the hood. Listening a little closer I can hear a leak. Guess I'll try replacing the vaccum disk on the heater control.

4th gens don't have a heater control valve under the hood. The blend door that is cable controlled is the only thing that regulates the amount of heat.

system drawing

Now, if you are having problems with the air not blowing where the mode selector says, then you might have a vacuum problem.

[94 formula]

Just flush out the heater core I just did mine last night and it works great now from not working at all.

[ZMAN_DIEHL!!!]

the selector is a vacuum operated valve
but the temp is cabled
my friend just had his blazer flushed for the same problem
it was clogged with a bunch of slimy looking dirt and crap like that

[CLWILSON]

I forgot to mention in the previous posts on this thread that my car is a 91 Camaro. As far as flushing the heater core I just replaced it about 3 weeks ago and it made no difference at all.
If someone thinks that it may have gotten clogged by something in the hoses immediatelyafter it was installed, let me know I'm not against trying anything to get heat. I really appreciate all suggestions. Thanks.

[ZMAN_DIEHL!!!]

well then I think we can rule out a clog
only thing to do is take the dash apart and look at the linkage
in the heater controls see if they became disconnected
look at all vacuum lines etc listen for hisses