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
Re: STILL runnin' hot @ idle Posted by Ari [Email]  (#2847) [Profile/Gallery]
(more from Ari) on Thu, 6 Jul 2006 05:15:45
In Reply to: STILL runnin' hot @ idle, knoxjoe, Wed, 5 Jul 2006 21:45:40 Members do not see ads below this line. - Help Keep This Site Online - Signup |
From your post, it appears that there are two separate issues.
The first is the outside air temp. That sensor is located on the air dam on the driver's side. As far as I'm concerned, it's main use is to let you know if the road is getting near icing conditions, and to marvel at how cold it is when the car starts up. Otherwise, it's really only useful when the car is at speed, and then only after it has been at speed for a few minutes. When the car isn't moving, heat radiating up from the road and heat pouring off the engine make a liar out of the sensor. If the cooling fan kicks on, it'll blow hot air from the radiator all over, and part of that over is over the outside air sensor. And the sensor has a thermal lag, so it can take a few minutes to read accurately.
Basically, the outside air temp reading is to be ignored unless the car is moving at speed.
The more important issue is the engine coolant temp. It appears that it reads OK when the car is moving, but not so good when the car is idling or moving very slowly. The first question would be if the cooling fan comes on when it should - after the car is warmed up, and if its idling for a while. If not, I'd suspect the thermoswitch you installed.
Next is the AC cooling fan. Look in the front of the grill, right about where the AC compressor is. That fan should come on when the AC clutch pulls in, and turn off when the AC compressor releases. With the car off, spin the fan blades to make sure they spin freely. If the fan is binding it will pull more current, and that could be causing the fuse issue. And the fan should be running as mentioned above. If not, that will make your overheating issue that much worse.
If that all checks out, I'd recommend going to a 82C thermostat AND an 82C thermoswitch. The stock thermostat and thermoswitch are 89C. I doubt you get very cold winters there (in Swedish terms) so the slight loss of heater capability at temps below 0F probably won't be an issue. The cooler thermostat will allow coolant into the radiator sooner. That doesn't help at idle, but the 82C thermoswitch will - the fan will come on sooner. 82C thermoswitchs were available from Townsend imports (haven't bought one lately), and some folks talk about a VW equivalent.
If the car is running cool at speed but not at idle/low speed, it is either the fan isn't coming on soon enough, or the radiator has lost efficiency. The cooling fan is there to replace the airflow the radiator gets when the car is underway. But the fan doesn't have the flow that a car at 60 mph has. So if the radiator has a marginal efficiency, the problem will show up first at idle/low speed. When you changed the coolant, did you flush the radiator? That may help. But if the radiator is badly crudded up (as a 14 year old car is likely to be), you may end up replacing it. That would be next on my list.
posted by 192.249....
, Thu, 6 Jul 2006 05:15:45 <-- Viewing This Message, Thu, 6 Jul 2006 10:02:34
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.
 |
 |
 |
 |
 |
