Greetings all, I recently bought a 2003 LW300. Nice car. Recently I noticed waterlogged carpet on the driver's side (only). From the AC? This car has automatic climate control so the compressor runs almost all the time.

Sounds like a windshield leak .... A/C and heater cores are on the passenger side.

Foolish question here -- does your L300 have a sun roof? Might be a clogged drain coming from there ....

No sunroof on this one. I'm trying to dry it out before the next rain comes to see what happens.

Other obvious point is to check the fit/condition of the weatherseal on the driver's side door.....

and any points along the firewall/base of front of engine compartment where a gasket might be torn/missing?

Have you looked at the underside of the vehicle to check for "holes the previous owner might have forgotten to mention?"