Re: Out out, damned heat!

[steveb@falcon.kla-tencor.com (Steven Buchholz)]

> Yesterday, when the temps broke 70 for almost the first time this
> year, my fresh air decided to blow only heat, even on LO temp.
> 
> I assume it is the temp control flap buried deep in the bowels
> of the car, so it will be a bitch to fix. Does anyone have any
> quick suggestions so I don't have to have the windows open all
> the time?
> 
... actually it may be the motor that actuates the flap.  On the 
5ks this isn't too tough to get at.  It is located behind the 
glovebox.  Upon further thought it may be easier to get at the 
business end of the cable by removing that thin plastic cover 
over the HVAC box ... the cable should be very accessible on the 
passenger's side of the blower plenum (the big white box centered 
in the shelf behind the firewall.

Boy, I'm coming up with all kinds of ideas today ... :)  You know, 
one thing that should fix the problem is to apply a vacuum to the 
coolant flow valve.  The fact that setting the system to LO doesn't
fix the problem indicates to me that the vacuum line is not intact,
because setting to low is supposed to close the heater valve.  IME 
this means that the vacuum motor that drives the recirc door has 
probably come off.  Can you hear the recirc door close when you set 
the system to LO?

I've been tempted to attach a hose with constant vacuum to that heater 
control valve during the summer.  I try not to use the A/C (i.e. the 
ECON setting), but the way the system is set up you will have some 
small amount of heating of the air by definition because coolant is 
always flowing through the heater core ...  Another thought has been 
to mechanically close the valve somehow ... or perhaps to put an old 
fashioned heater valve in line and set the flow rate manually.  Hey, 
I really like that idea ... I think I'll try that on the 5k myself!  
This would allow me to set the flow rate as the seasons change ... and
if it suddenly gets cold in the summer all I've got to do is pop the 
hood to restore full flow ...

HTH!
Steven.Buchholz@kla-tencor.com
San Jose, CA (USA)