Puddle under 2008 Subaur Impreza

I have a 2008 Subaru Impreza. When I start it up there is a puddle on the ground directly under the driver’s seat. I have taken it to the Subaru dealer, they have looked underneath it and have found nothing. Since it is not directly under the engine it does not appear to be oil or any type of liquid like that. I have soaked it up with a paper towel and it appears to be water. It is soaked up by the ground in my parking space so does not stay around like oil would. I am puzzled at this point. I would like to figure out what it is so I do not have major problems in the future.

Do you have a sunroof?

No I do not have a sunroof.

“It appears to be water.”

If it is water, then this situation is not something that relates to your car mechanically.
However, I would suggest that you soak up this fluid with a clean rag, and then squeeze the rag into a clean container. That should allow you to examine the fluid in order to be sure of what it is.

If it is water, then probably you are just seeing condensate from your HVAC system pooling on the ground. In case you are not aware of it, the A/C compressor runs when you use the defroster setting of your HVAC system, so if you have been running the defroster at all, that may explain a puddle of water underneath the car.

The cooling system contains a mix or coolant and water, and that fluid does not look, smell, or feel like water.

The windshield washer reservoir should contain a mix of water and some type of alcohol/ammonia mixture, along with dye, and this also does not look or smell like water.

The only other fluids in your car are petroleum-based, and certainly do not look, smell, or feel like water.

I can’t tell you what the source of this “water” might be, but it certainly does not seem possible that it is coming from your car–unless it is condensate from the HVAC system.

In addition to the HVAC drain you also probably have cowl drains at the bottom of the windshield. They drain the runoff from the windshield area to the bottom of the car rather than channeling it through the engine compartment. Any little bit of rain or reason for condensation could easily produce a puddle. For piece of mind you could locate them and figure a way to make sure they’re clean.