I've got a 2000 Discovery II it's been leaking on the carpet of the passenger side floor, and can occasionally hear water swishing around from the passenger side. Sounds like it's coming from behind the glove box. Today I noticed smoke coming from the air vents. What could be causing this?

 

The water sloshing sounds like air in the cooling system- fill with coolant and burp as needed. Smoke might not be so good. Got a fire extinguisher?

 

I'm guessing a failing heater core. I once had a core fail (not the LR but they're all the same) and along with the wet carpet, I had lots of "smoke like" water vapor coming out of the vents.

Do you smell antifreeze?

 

I do have a fire extinguisher, hopefully it doesn't come to that. Could the heater core also affect my AC?

 

What trouble do you have with the AC?

 

sounds like heater core leaking....

 

It just hasn't been working at all. Even on full blast I can only feel it a little bit while the vehicle is actually moving. How would I go about fixing a leaking heater core?

 

First you need to determine if its coolant or rain water from the sunroof.

The sloshing is air, you need to bleed it until you get rid of that noise.

A heater core problem, you need to swap it out by removing it. Download the rave for the details.

 

Replacing the heater core on these is a horrible job. You gotta remove the entire dash assembly. But if the carpet is wet, look up under the passenger kick panel, you'll be able to see the drip. The AC could be a different issue all together, but I suspect there's a leak in that system due to the heater core cracking.