RE: heating woes, continued

["Titus, Brian (NJAOST)" <BTitus@njaost.ml.com>]

Thanks for your help. Here's what the lunchtime parking lot excursion has
revealed:

I found the programmer and observed the Bowden cable to be stuck in the cold
position, pointing to the left. (Note: the heater control valve at the
firewall seems to be functioning normally) When I switched to 'HI', the arm
had trouble moving, but with some 'assist' I got it to travel to the hot
position. Then I got heat from the vents. Various LO to HI tests indicate
that something is sticking -- either the cable or the flap. At one point I
was getting a clicking sound from the little motor/arm as it was unable to
force the cable to move.

What should I plan for the 2:00 coffee break? :-)

thanks again,
Brian
885ksq

> -----Original Message-----
> From:	Dan Simoes [SMTP:dans@ans.net]
> Sent:	Monday, March 23, 1998 11:46 AM
> To:	BTitus@njaost.ml.com
> Cc:	quattro@coimbra.ans.net
> Subject:	Re: heating woes, continued
> 
> > 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 |