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Discussion Starter #1
I'm not sure if this is normal or not...

The heater in my 2000 9-3 is pretty wimpy. It takes about 25 minutes for it to get comfortable inside with the heat all the way up, the fan on 2, and it being around freezing out. Not a huge deal yet, but it gets a LOT colder here (Vermont), and I am concerned about how well it will keep me warm on those days that its below 0ºF.

You can hold you hand right by a vent and its merely warm, never hot (whereas on my Miata for example, you will virtually burn yourself).

My assumption is that this is not normal, especially for a swedish car that has a convertible variant (mine is a 5dr). Anything I should be looking for?
 

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If the temp guage is not moving much, I think I would replace the thermostat. If the guage goes up near halfway, I would look at the blend door in the plenum. I've got a 98 ragtop, and the heat seems fine. I'm in Vermont too, so I sure will need it:confused: Let us know how you make out.

KGBrown,
Hartland, Vt.
 

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Then, I would look at the blend door. Or, heter core blockedHeater hose kinked? If the coolant is hot enough, your not getting enough flow. After that, I'm out of ideas.
 

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saabiturbo said:
The temp gauge runs to about 1/3rd of the way up, unless I am sitting in traffic for a longer period.
You have the classic symptom of a failing thermostat. The temp gauge should go to a 9 o'clock position within about 5 minutes, and stay there.

Our temp gauges are NOT linear, and do NOT show true temperature. The temp sensor on the block is connected to the ICE module, and the software controls the needle of the gauge. It is programmed to put the needle dead-on at 9 o'clock, when the temperature is in an acceptable range. The "acceptable" range is programmable.

The default is a rather wide range: Temp gauge at mid point (9 o'clock) corresponds to 85-115 C, a full 30 degrees C, or 54 degrees F.

A little below that position, or a little above, actually means that the engine temp is much below, or much above where it should be.

When the weather gets cold, cold air flows over the radiator while driving, and the coolant is at a lower temperature than in the summer. The thermostat should close to limit the flow of coolant, so the engine (and heater core) can warm up properly.

Our thermostats fail open. Therefore, when the thermostat fails, the engine never heats up while moving at highway speed, and neither does the heater core (or your feet).
 

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saabiturbo said:
Would this also explain why my temp gauge sometimes doesn't register anything at all?
Maybe. By that you mean the needle is all the way at the bottom?
 

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Discussion Starter #8
Yeah, sometimes... most of the time it seems to register correctly (well register at least), but sometimes it just goes straight to zero (no other instruments ever do).
 

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saabiturbo said:
Would this also explain why my temp gauge sometimes doesn't register anything at all?
No.
The key is 4 to 6 minutes warm up time.
Your gauge transmitter MAY be failing - or there is some corrosion on the connection.... or the gauge could be bad...
At the dealer we would use a known good gauge to check out these systems.. but the old cars were far easier to work on..
 

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earthworm said:
At the dealer we would use a known good gauge to check out these systems.. but the old cars were far easier to work on..
The sensor is not hard to check, it does not even have to be unscrewed from the block, just unplugged from the connector, and resistance checked with a multimeter.

If you want to do an exact test, removing the sensoe, and checking its value immersed in boiling water and ice water is pretty close to a perfect test.

Typical resistance values are somewhere in the Haynes manual.
 
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