My Boxster used to do the same. Ultimately, I found that the water pump was weeping and the coolant was evaporating before it could drip. I didn't do anything about it until my water pump started actually dripping.
This is what it looked like:
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1999 996 C2 - sold - bought back - sold for more
1997 Spec Boxster BSR #254
1979 911 SC
POC Licensed DE/TT Instructor
My Boxster used to do the same. Ultimately, I found that the water pump was weeping and the coolant was evaporating before it could drip. I didn't do anything about it until my water pump started actually dripping.
This is what it looked like:
That's exactly what i was going to say. You wouldn't see a puddle for that slow a leak but you will spot signs of water evaporation underneath.