Heak soak thermostat question. I have been thinking....
08-06-2004, 03:50 AM
#1
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Heak soak thermostat question. I have been thinking....
that it is a good idea to change the auxiliary pump and fan switch to a lower temp than the standard one. The one thing I am concerend about which may be already catered for is this.
If the thermostat is chnaged to one that switches at say 100ēc, then it will obviously come on more often when stopping after a journey which will reduce the engine bay temp whihc is good. But, will it come on when actually driving and that temperature is reached?
If is does, then this could cause other more significant cooling problems because the auxiliary pump will interfere with the normal water flow created by the engine's water pump and also it will wear out this pump when it not needed.
The only answer to this is if the auxiliary circuit is not engergised until the ignition is switched off. Then, my concerns are answered. Does anyone know if this is the case?
I do like the idea of fitting the vented RS6 arch liners as well. These must help if they are designed to cope with the heat that the V8t can produce.
If the thermostat is chnaged to one that switches at say 100ēc, then it will obviously come on more often when stopping after a journey which will reduce the engine bay temp whihc is good. But, will it come on when actually driving and that temperature is reached?
If is does, then this could cause other more significant cooling problems because the auxiliary pump will interfere with the normal water flow created by the engine's water pump and also it will wear out this pump when it not needed.
The only answer to this is if the auxiliary circuit is not engergised until the ignition is switched off. Then, my concerns are answered. Does anyone know if this is the case?
I do like the idea of fitting the vented RS6 arch liners as well. These must help if they are designed to cope with the heat that the V8t can produce.
08-06-2004, 04:14 AM
#2
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Do you mean like this?
According to the S4 self study guide, the afterrun system does not activate until the ignition is switched off.<ul><li><a href="https://forums.audiworld.com/s4/msgs/1629709.phtml">Lower Temp Switch Thread from QCRAZY</a></li></ul>
08-06-2004, 04:58 AM
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Yup with ignition off. If you lower the temp too low you
will really be taxing the battery. I'm sure a building full of engineers have calculated whats needed to bring the temp down while ensuring that the friggen thing will start when you want it too. Lowering the temp when the system operates is really for more for your benefit than it is for the car.
08-06-2004, 05:02 AM
#5
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I was thinking that when I read the recent post about this...
I figured that if the original switch is at about 112ē the one to fit would be the one that is set for about 102ē or so, if you go to the lower one at about 90ē, it will be on all the time and flatten the battery very soon.
08-06-2004, 05:11 AM
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The thing times out at 10 minutes no matter what the temperature is at that point.
It looks like the time setting was arrived at by the Audi engineers based on the juice required to run the small after run coolant pump and run the front fan at low speed without overtaxing the battery.
I've been running this mod for about a month.
I've been running this mod for about a month.
