E39 Wet Floorboard, Driver Side Leak...

[bob in houston]

I was vacuuming (sp?) my 2000 E39 and noticed that the driver floor carpet was very wet. It's definitely water. I wash my car often, 2x per week, and the wheather has been very wet here in Houston as of late, but I had not noticed the wet carpet before. Recently, I've been using the "Auto" feature on my A/C. Could the drain on the A/C be clogged? My old E34 actually had the drain pipe slip off the condenser in the center console area, but the E39 drain is hard to locate. Any help out there?

[billB]

Are you sure it is your AC?
1. Make sure this is not a problem of plugged Front sunroof drains. They drain out of 2 openings near your L/R front jacking points. The rear drains travel through your trunk to drain; these rubber hoses are a must.
2. Also check 2 drains on the firewall under the hood—look for them at both edges of the plastic housing/grill after you remove the plastic cover to gain access.

Note: If this is the case you may park your car with front facing uphill (if any) to minimize the leak..
regards
billb

[bob in houston]

bill, no i'm not sure it's a/c. but the carpet is actually dry near the center console next to the gas pedal, so you're right, it's not likely. i pushed some wire about 3-4 ft into the sunroof drain hole before i couldn't get it in any further. after looking at the sunroof seal, the seal is in very good shape (tested it by closing the sunroof while placing a sheet of paper in seal in several areas, couldn't pull the paper out after closing). the "plastic cover" you mention, are you referring to the cover over the wiper motor/mechanism? and is the drain hole for the sunroof accessable without removing the wheel well cover? thank you for your help. bob in houston

[billB]

Bob
YES. Take a quick look at the underside of your rocker panels. By the jacking points there should be a tiny opening on each side for drainages, they tend to accumulate a lot of debris once clogged think in terms of rocker panels channels getting over filled with water seeping into carpet as such water gets trapped into channel/no where to go especially if the front of the car facing downward on uneven driveways (escape routes are the holes under carpet for wiring harnesses etc not water airborned dripping from the skies above)

Important Notes:
1. For a remote possibility and future reference? When installing a new windshield on BMWs; NOT TOO SMART glass installers tend to block the drains at the top of the windshield!!
2. Drains Testing: pour water into the sunroof front holes-nose down/steep driveway etc- water should rush out of rocker panel's outlets 6-9 inches from the front edge of both rocker panels. Do same in Reverse/nose up/steep driveway-water rushes out of the back side!
3. Flat screw driver will do the trick-outlets are not round/more of a crack in the rocker- I simply drilled through these cracks with a very tiny drill bit to enlarge it
Good luck cowboy!
billb