Re: heating woes, continued

[Dan Simoes <dans@ans.net>]

> the heater control valve definitely moves its
> full travel. So, if there is coolant in the system (and not on the ground),
> the engine is warm, the control valve actuates, and the fan blows, why no
> heat to the cabin? Blockage in the heater core or hoses? hmm...

You're talking about 2 different things here.
Here is what I would check (based on a CQ, but similar?):

- in the engine compartment, there are two hoses at the firewall. 
  Feel them both - are they both hot?  Odds are they are not.

- one of those hoses, probably the leftmost, leads to a plastic
  plunger-looking doohickey.  This is the heater control valve,
  which is controlled by vacuum.  Try moving it by hand, or 
  note the position at 72deg, now move it to LO (temp) inside
  the car, come out and see if it moved.

- if this valve is moving, and inside the car the arm is cycling
  from hot to cold, the next step is to check the CC head diags.
  Press and hold the outside temp button and the OFF button.
  Pressing the warm/cold will cycle you through the channels,
  the most important ones are channel 1 (should read 00, 15 if
  there is a problem with the temp regulating motor, if you have
  one), channel 8 (actual position of the temp regulating motor)
  and channel 9 (specified position of the trm).  If channel
  8 is off by more than 3 units, in relation to channel 9, there
  is a problem with the temp reg motor.

Hope that helps.

| Dan |