5K A/C Programmer

[spsherm@ibm.net]

I've got a question or two for the experts out there about the operation
of the "dreaded" AC Programmer (the little black box with all the air
switches under the glove compartment).

I've been improving a "no air out of the dash vents" problem.  First I
found and corrected a couple of detached vacuum hoses.  That helped alot
but I still got 50% failures on getting dash air.

Then I took out the programmer, checked the dash vent vacuum motor for
leaks (it was fine, as usual). Re-rubber cemented some loose air lines
in the programmer, checked for bad solder/pc board, and put it all back
together...

Now I get dash air >80% of the time.  But the econ and ac air still
sometimes come out thru the defrost...  Going over a bump or a sharp
turn (and sometimes doing nothing) can cause it to switch to or from the
dash vents.

Another thing I notice is that my idle speed will go down by 300rpms if
I select the defroster but only the defrost setting (I've tried them
all)???

My take on all this is that one or more solenoid valves are leaking 
(those valves are suppose to seal tight to the engine vacuum when not in
use). The odd thing is that no other controller setting except defrost
will give the low idle speed, so one or more of these things are
leaking. 

I can probably find out wich line, by pinching off the lines one (or
more at a time).  My question is what to do after I find one or more
leaking valves?  Whole new unit (a rebuilt one is not likely to be
better that what I have)?  Has anyone tried to r&r one of these valves?

I remember some conversations about this unit being the same as a GM
one?  Does any GM line sell the solenoid valves separately?

TIA

Steve

My