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Torque Pro shows both my VAG vehicles running at 208 +/- 3 even though both dashes show the needle sitting at "190".
This has been the case with multiple ECTSes.
 

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Yes.
 

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2000 Passat B5 wagon, 4-Motion, 2.8l ATQ
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Discussion Starter #24
I tried another test: Made a video of the coolant overflow tank, at idle, 1K, and 2K RPM, with warm engine, then shut-off. Only after shut-off could I see coolant being pumped [by electric pump] into the reservoir via the small hose [front/top].

I thought coolant should be flowing in when the engine is running? The tank is 20-years yellow, so it's possible I wouldn't see the flow if it were not projecting as far as when driven by electric pump.
 

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2000 Passat B5 wagon, 4-Motion, 2.8l ATQ
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Discussion Starter #25
Does the aux fan kick in to assist the viscous fan if temp goes up too high?
With my [frustrating] Climatronic system, it seems the aux. fan only runs when not in Economy mode [where it runs full-time]. My fan is a bit noisy, so I can hear it, plus I can hear the relay switching. The coolant temp has gone above 220F (measured via OBD) in Economy mode, and I still don't hear the fan.
 

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Perhaps the temp sensor for the fan is bad. It's on the lower radiator hose.
 

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With my [frustrating] Climatronic system, it seems the aux. fan only runs when not in Economy mode [where it runs full-time].
That's how it's supposed to work, and the manual AC works the same way: the electric fan runs on low speed whenever the AC is turned on. It will call for high speed if the refrigerant pressure goes really high, e.g. sitting in traffic on a 90°+ day,

As PZ says, the control of the electric fan vis-a-vis the coolant temperature is from the two-stage temperature switch in the lower radiator pipe. So, it's looking at the coolant temperature after the radiator, the coolest point, verses the coolant temperature sensor that's at the hottest point.

In my 19 years experience with the cars, the coolant almost never gets hot enough to run the electric fan, but I'm in Ohio.
 

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With my [frustrating] Climatronic system, it seems the aux. fan only runs when not in Economy mode [where it runs full-time]. My fan is a bit noisy, so I can hear it, plus I can hear the relay switching. The coolant temp has gone above 220F (measured via OBD) in Economy mode, and I still don't hear the fan.
That is normal.
 
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