harmonytom

Drove my 2010 E350 for dinner under heavy rain fall on Friday, today found out area under carpet on the passenger side (only) are all soaking wet, do not know where the water coming from, anyone knows what is the cause of the leaking and how to stop it happens again ?

mspearl95

There may be a plug in the floorboard thats missing, or it could be that one of the sunroof drain tubes came loose. That happened to my LS400, the right front sunroof drain tube was disconnected, and water would pool on the the front passenger floor.

RickC5

Do a search about floorboard plugs. There is a long thread on here about those. Our '08 had several plugs missing, and others installed wrong. After plugging up the open holes on our car, it is much quieter, and I'm sure it is less prone to water coming in too.

harmonytom

Thank you all!

igzy

I suspect either loose or clogged sunroof drain hose (as mspearl95) hole in windshield sealer. Did you have the windshield replaced recently? Also any accidents?

garsarno

Ditto windshield. Had windshield replaced on '99 Town car years ago. Wet carpet = poor seal at base of windshield in this case.

mspearl95

the way i discovered that the leak was coming from the sunroof was to use an air compressor to blow air through each of the drain holes, and listen to where the air sounded like it was coming out at. 3 of them sounded like they were coming out in their proper locations, but the 4th sounded like it was blowing out underneath the headliner, which of course it was. Easy test to do if you are hunting for the source of your leak.

igzy

Ditto for compressor... When I was troubleshooting my father-IL's car, I just took them off and blew into them. One was clogged. I did get dizzy getting it unplugged :P LOL