Mold smell when I roll down front windows

Post by **FireFox31** » 12 Mar 2021, 15:40

What could cause a mold smell when I roll down the front windows on my new-to-me 200k mile 2000 V70?

It has a sunroof which doesn't seem to close perfectly; the back edge of the glass has a hard time raising/lowering past the metal roof. Driving through the car wash drying blower, I felt a little air get past the glass which tipped me off to this issue. Shortly after, I didn't close it properly before rain and a quarter cup of water fell from around the glass when I put the car in reverse.

Yet, I don't smell or see mold up around the headliner. And I don't smell a problem while driving with the windows up. I drove with them down for 30 minutes on multiple occasions to air it out, yet still I get the mold smell each time I roll them down while driving.

Thanks for your help.

Post by **scot850** » 12 Mar 2021, 16:27

Check the following:

1) Check all door drains are clear (no water sloshing in the doors)
2) Lift the carpets, fronts and rears. Don't just fell the surface as they have a rubber liner which may mean the tops fell dry but water has gathered under the carpets.
3) There are drains in the front of the car in the engine bay that can get blocked. There are 2 under the window wiper motor cover that can get blocked with old leaves and stuff. The passenger side one especially is right beside the cold air intake for the cabin air.
The LHS one is by the fuse box make sure that one is also clear!! Tod get in there you really need to remove the wiper arms and the black plastic cover plate. While in there make sure the cabin filter is not blocked and is clean and not wet.
4) There are 4 drain pipes from the moonroof. Basically one at each corner of the moonroof 'sandwich'. These can block and or split. If they split it is usually near the moonroof cassette end. If they are split at all you will find out as front seats will get wet or rears. Check they all drain. The rears drain into the trunk if I recall in the sedan and in the wagon just behind the rear inner wheel fenders.
5) Get someone to spray water around the tops of the door seals and the area around the rearview mirrors. Worn seals and door hinge pins can allow water to get past the seal around the mirror. Also check the front windshield seal for leaks.

Lastly, it may not be mold but a leaking heater matrix. This is under the LHS front dash behind the radio. You may be able to see traces of leakage with a flashlight and some rumaging under the drivers foot well. Small amounts may show trace tracks in dust near the gas pedal area.

Good luck.

Neil.

Post by **abscate** » 13 Mar 2021, 04:37

Do you get the smell when you roll down the windows at rest or only when driving? It could be that you suck air from * somewhere* when you drive and the window opening is the vacuum that moves it. Sorry, that’s poorly written.

Post by **RickHaleParker** » 13 Mar 2021, 07:04

Have you turn on the turned on the blower fan to see if it coming from the climate control unit?

Might be able to use smoke to track the air flow back to the source.

Post by **FireFox31** » 13 Mar 2021, 11:36

Thanks, this is great information. My first check is the moonroof drains. When that little bit of water spilled out, I found the first two, so thanks for saying there are four.

I plan to proactively replace the heater core, assuming it's original and going to fail if it hasn't already. My coolant level is dropping suspiciously.

I don't think the smell is from the blower system since I used it all winter. There were chipmunks living in the air filter box and I still have to finish cleaning that. I kind of want to remove and bleach those large plastic pipes.

While rehabilitating this V70, I'm looking for the largest problems first. For me, mold in the car is probably more of a deal breaker than a blown head gasket or leaking transmission.

Post by **FireFox31** » 27 May 2021, 23:25

The sunroof is leaking slightly at its front corners letting water on to the headliner, causing the mold smell. It doesn't seem to leak when it rains (no water on the seats or floor). When I stop from reverse with water on the roof, a little bit drips in from those corners. The metal frame around the sunroof glass appears rusted. Perhaps a new sealing strip, part 1390349, $215 list, $175 at Volvo Parts Web Store. Has anyone successfully repaired a leaking sunroof?

It appears that the headliner is no longer available so I'll have to clean it. Can the headliner be removed and replaced, allowing me to check for mold underneath?

Post by **scot850** » 28 May 2021, 17:19

Also check the drains are not leaking from the sunroof at the corners.

I may have mentioned before, but I also had a car that leaked from the top of the wind-shield. Again, only leaked under certain conditions.

The frames to corrode as if I recall they have aluminum and steel in them. It may be worth finding a better one if you can.

Neil.

Post by **RickHaleParker** » 28 May 2021, 18:09

FireFox31 wrote: ↑27 May 2021, 23:25 Can the headliner be removed and replaced, allowing me to check for mold underneath?

Yes and when you have it out you can strip and recover the headliner with new fabric.

Post by **FireFox31** » 09 Jun 2021, 21:01

RickHaleParker wrote: ↑28 May 2021, 18:09
FireFox31 wrote: ↑27 May 2021, 23:25 Can the headliner be removed and replaced, allowing me to check for mold underneath?
Yes and when you have it out you can strip and recover the headliner with new fabric.

What do you mean by "strip and recover"? I assume the headliner is the fabric, so recovering it seems to mean replacing all of the fabric on the roof. I'll search the forum to see what info is there.

Seems like there's foam between the headliner fabric and the roof metal. That foam has flattened out at the spots where I smell the mold. So, I may need to replace some of that foam as well. Maybe cut scraps off a donor? Or take the whole headliner from a donor??

Post by **FlyingVolvo** » 09 Jun 2021, 21:14

FireFox31 wrote: ↑09 Jun 2021, 21:01
RickHaleParker wrote: ↑28 May 2021, 18:09
FireFox31 wrote: ↑27 May 2021, 23:25 Can the headliner be removed and replaced, allowing me to check for mold underneath?
Yes and when you have it out you can strip and recover the headliner with new fabric.
What do you mean by "strip and recover"? I assume the headliner is the fabric, so recovering it seems to mean replacing all of the fabric on the roof. I'll search the forum to see what info is there.

Seems like there's foam between the headliner fabric and the roof metal. That foam has flattened out at the spots where I smell the mold. So, I may need to replace some of that foam as well. Maybe cut scraps off a donor? Or take the whole headliner from a donor??

The original headliners are a fabric with some thin spongy foam on top of a big board of sorts. I don't know what the material is, but the best way I can describe it is a mix between cardboard and fiberglass. I'm sure someone here knows the actual name, but I'm drawing a blank.

To re-do the headliner, you peel off the fabric, scrape off all the foam off the board, then reglue new stuff. I had a shop do mine on the XC and the 850. I did the labor of removing them, and both times was about $250 to have it professionally done. I'd rather have it go to someone who can do it with their eyes closed. Pulling the headliner isn't super hard, but it is tricky and time consuming, especially by yourself.

I'd say pull your headliner and take a look if anything is growing under there. Depending on how bad it is, it may be salvageable provided you stop the source of water.