1985-1998 [Subscribe to Daily Digest] |
 | [Main 9000 Bulletin Board | BBFAQ |
Prev by Date | Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
Good info Posted by Ari [Email]  (#2847) [Profile/Gallery]
(more from Ari) on Fri, 28 Mar 2003 09:06:37
In Reply to: Let me try to answer these questions for you, adam  [Profile/Gallery]
, Thu, 27 Mar 2003 19:07:49
Members do not see ads below this line. - Help Keep This Site Online - Signup
|
Yes indeed, the heater core always has flow and is always hot.
I doubt it's the water pump, for a few reasons. First, water pumps don't usually fail by slowly losing the capability to pump. The typical failure is for the seal to leak. I've never seen a water pump just get less efficient. Also, if a pump did fail to pump as well, by the time you saw this as less flow to the heater core, the engine would have melted down to slag. Since your engine isn't a steaming pile of slag, it's safe to assume the pump is pumping.
There is a mixture flap, interestingly called the 'mixture flap', that combines outside air that has come from the A/C side with hot air from the heater core. The position of that flap is controlled by a servo in the dashboard, and the servo is controlled by the ACC.
There is a fault where the flap arm breaks, but that shows up as being stuck on either full hot or full cold all the time.
I see a few possibilities -
ACC servo problems - the servo just stops working after a while. To check, run the ACC self test. This consists of hitting AUTO and VENT at the same time. See http://216.78.172.244/climate_control_folder/acc2index.htm
for more info on that.
The other one has to do with the thermostat. Typical 9000 operating temp is around 9:00 on the temp gauge with the stock 89C thermostat.
The other possibility is that Saab uses a three-stage thermostat - at high temps, it actually bypasses the heater core and puts full flow to the radiator. If your thermostat is doing that, you'll lose heat. If you have a problem in the radiator - blockages, clogged, or just stuffed with dead bugs, the engine temp would run higher, but the thermostat would go to the 'third' position and cut off flow to the heater core. I'd expect to see very high engine temps, but you might have a combination of inefficient radiator and a bum thermostat.
If your thermostat is more than two years old, three tops, replace it. Thermostats are moving parts and wear out.
posted by 192.249....
, Thu, 27 Mar 2003 16:10:06, Thu, 27 Mar 2003 17:01:12, Thu, 27 Mar 2003 21:31:23, Thu, 27 Mar 2003 19:07:49, Fri, 28 Mar 2003 09:06:37 <-- Viewing This Message, Fri, 28 Mar 2003 17:25:23, Thu, 27 Mar 2003 16:56:43
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
 |
 |
 |
 |
 |
