my understanding is that there are 2 water pumps one that runs on the engine and an electric one for during autostop. That is why there is an extra coolant reservoir under the hood. My autstop has worked with the temp as low as about 170snapped a photo in auto stop
edit it
auto stop worked when it was below the 210 spot... but as each day goes on we are still learning how it works
at which point it works etc...
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