Crew Van - black goo underneath floor covers

I recently had the small floor mats up that live behind the driver and passenger pedestals in my 2016 crew van (im in British Columbia). I found all this gross, slimy black goo under there so decided to dig some more. I pulled up the center matting between the two seats and lifted the vent ducting to find the mess that is pictured. I suspect the warm air through the vent is turning the rubberized stick on mat that MB put in random spots to goo where it has been chaffing. Then it runs out the side and generally makes a mess everywhere. When I lifted up the wiring loom that runs between passenger and drivers seat the plug has been pulled in a effort to try and get the goo to run down there I think - I guess the service techs did that during the last service. The hole also appears to have some corrosion already.

Anyone else have this problem? Pics attached of (1) the mess (2) cleaned up a bit and showing the chaffing spots (3) minor corrosion starting under wiring loom area.

Is it possible that's undercoating that sprayed up from below?

No it cant be, becuase i clean it up and it comes back.

It is a sound deadening pad which is being 'attacked' by something chemically, ie a solvent.

If you look in your first two photos you can clearly make out the extent of the pad as it is discoloured compared to the surrounding paintwork.

You could possibly seal it with a fresh coat of paint but may have to resort to a specialist 'sealer' to prevent it bleeding through again.

Keith.

I also have a 2016 Crew and there is nothing like that going on underneath the floor. That vent really doesn’t get hot (barely warm really) so I’d be surprised if it was heat melting anything. It almost looks like someone spilled a can of Coke down the hole where the parking brake cable goes through the floor foam. The mess doesn’t seem to have pooled in the channel between the seats so it must have originated further back/downslope.

My van also had those two holes open when I got it; I plugged the holes with rubber caps that I had lying around.

I'm still under warranty and a no-charge maintenance plan. Is something a dealer would be expected to fix?

I agree it looks chemical but nothing has ever been spilt down there.