I have a 2001 eclipse. Water leaking onto driver side of floorboard. There is so much water it is puddling.I am not sure if it is ac drain or heater core. I can't find ac drain to see if it is clear. Thanks for your help and suggestions.

I recently had this repaired. As it turns out, the evaporation reservoir separated from the firewall. I was fortunate enough to have a good mechanic that completely diassembled my dash to locate the leak. He did not make up some lame diagnosis. I was unfortunate enough to have to pay for the extensive work, but it is worth it. He resealed the heater core compartment to allow the water to drain out properly. I spent many hours searching for an answer in the internet. this is the only solution that I know of.

It's actually the a/c drain that goes thru the firewall on the driver's side. the hose that goes thru the firewall is too short (appx 1"), and there is a foam seal around the hose which breaks down over time, allowing water to run back into the driver's side floorboard. remove battery, battery mount, air filter, and use some really good gasket sealer to seal around the hose. also, I glued another piece of hose onto the existing hose to extend it out 3-4 inches from the firewall. this stopped the leaking, and now I have a dry driver's side floorboard.

Its not the heater core. no smell of anti. my mother in law is having the same problem and it is just water on the driver side not the passenger side. i will know later tonight when i pull every thing out.

It most likely the heater core