I tried to search for this and came up empty-handed. Here is my problem. i have water that is dripping onto the far right side of the passenger floorboard. yesterday there was quite a bit of it (roughly a liter), and figure that there is some sort of fitting that is lose that is causing this to drip internally instead of externally. I have looked all over for this and can't figure out where it is.

Does anyone know if this is a hose/fitting/valve, and where it is/what it looks like?

I am worried that if there is too much water there may be rusting under the carpet.

Please help.

Have you been using your AC a lot lately? If it's just water, it's likely condensation of the evap. There's a drain hole leading through the firewall. It must be clogged.

Mine was leaking from the Rh side windshield gasket.

Took me quite a while to figure that one out. The gasket was kind of old and just would not seal. Fixed it by caulking with black silicone gasket sealer.

I have looked and am still not sure where the drain hole is. I pulled the carpet back a bit in the firewall area, and saw a cap (about 1 inch in diameter) that looks to be holding the pad up against the firewall. Do I need to pull this back too? It wouldn't make sense to get to the drain hole/plug.

Or, can this be accessed, under the vehicle, or from the engine area?

In short, I need a laser-guided location for this, and would be extremely grateful if anyone could point this out.

I am slowly building a pond in my passenger side, so the sooner the better.

cheers

You didn't say what year it is.

You didn't confirm if you're using your AC a lot lately.

You didn't say if you think it's just water or something else, like coolant.

Om my 88 there's a black elbow coming from the firewall (inside the engine compartment) just behind the charcoal evap canister near where the coolant lines go to the heater core and your AC lines to the evaporator.

On my 97, the drain hole is in the same place. I used compressed air with a blow nozzle to blow it out.

missed the basics:
96 XJ 2wd 4.0

using AC a lot, and problem only occurs when AC is on, or shortly after shutting off (after condensation accumulates).

I will look in the engine compartment for it this evening. Thanks for the advice!

Thanks for the comeback. Yep, most likely the drain is clogged. If you have the elbow there, it may be difficult to reach from above. You should also be able tog et at it from below.