Hi all. Been a long time since my last post. Our 2007 was running great, and eventually got downgraded to a sitting/spare car that our daughter learned in, then drove for grade 12.
We started to notice the musty smell a long time ago, but I finally dug into it this past month.
I read tons of posts about the usual culprits of wet floors, Butyl patch, grommets, sunroof drains, firewall seal for hvac tube etc.....did it all.
I also conditioned all the weather stripping and cleaned the mildew off the door window seals.

Where our car is a sieve, is the door panels.
Why does this car not have the poly sheet and the gooey black glue that every other car seems to have??? Even our cobalt has it. The HHR has a foam liner loosely set in place with a bead of glue.
The water is sliding down the glass, into the door and splashing off the window motor, or other things, and then getting into the back of that foam liner. Then it comes down to the bottom of the door panel and leaks onto the inside of the weatherstrip, and into the car. All 4 doors to varying degree.
I have siliconed 6 mil poly as best as I can, and just redid the first 2 that I did. Water test tomorrow. Been at this for weeks, and its getting old.....lol.
Have any of you had to seal your doors? Did you just re glue the foam piece, or did you add poly over the openings? Did you end up replacing the whole door seal?
Any insight would be much appreciated.
Thanks very much.
Corey.

 

Welcome back, I didn’t experience this problem with Oldblue, my 2007 LS. When I replaced the door handle, I noticed the foam panel was adhered with black butyl adhesive. No water in the doors, I had the upgraded pioneer seven speaker system, I wonder if that had something to do with it? My 2011 has the same set up.

 

Weird. My 2007 also has the pioneer system. The glue used on the foam is like a rope, but its the same colour as the foam liner. I wonder if that because it became unstuck, what water was getting inside the liner was not being funneled back into the door through the little holes at the 2 lowest points of the liner. I assume those are to drain water back into the door.....
This happens during strong rain, or direct hose flow. I guess my window seals are worn enough to allow too much water into the door.....
So far, my plastic patching is working. It rained during the night and light rain today, no water on floor. I might have to invest in those weather tech gutters to reduce the water that flows down the glass.....

 

GM maybe never tested these cars in a climates like the Vancouver area, which can be challenging for cars parked outdoors. Depending exectly where you are, things can be very damp and it seems nothing ever dries out.

When it comes to mold and mildew, never wait to address it. If nothing else I’d park it in the sun whenever possible, in various directions. Thorough drying kills mildew.

 

Mine I used 100% clear silicone & run a bead around the door boots that feeds the wires thru.. That was just a precaution very long ago.