Car cover, mold/mildew issue

[futureZ]

Anyone have any insight as to why I ended up with mold/mildew spots on my car after putting a cover on in the garage? This was during the summer and it can get humid, not sure if this may have had anything to do with it.

Washed and dried the car, put the cover on and it sat for a week or so. Took the cover off and found the spots on passenger side of front bumper, headlight and fender. It did come right off with a detail spray.

I’d like to cover the car for the winter, however I'm nervous to leave the cover on now. Very nervous due to it being a convertible.

[Coz3z3]

Have you washed the cover? I would try that and do a test run. Is it a quality, breathable cover?

[swampcritter]

Could be moisture from the concrete floor.Do a moisture test on it. Cut a 2' X 2' piece of clear plastic and duct tape it around the edges of plastic to seal it to floor.Wait 24 hours and see how much moisture you have under plastic.

[futureZ]

Originally Posted by Coz3z3

Have you washed the cover? I would try that and do a test run. Is it a quality, breathable cover?

It’s a black satin cover from carcovers.com. I did not wash it, I’ll do that next.

[futureZ]

Originally Posted by swampcritter

Could be moisture from the concrete floor.Do a moisture test on it. Cut a 2' X 2' piece of clear plastic and duct tape it around the edges of plastic to seal it to floor.Wait 24 hours and see how much moisture you have under plastic.

I forgot to mention that the floor was paved over concrete the last time I used the cover. Not sure why previous owner did this. I’ve peeled up half the garage, where the camaro parks. It’s now just concrete. I’ll try the plastic trick and see about the moisture.

[gilbert85295]

Maybe the car was still wet underneath when you put the cover on

[1JEWLDSSRS]

Originally Posted by gilbert85295

Maybe the car was still wet underneath when you put the cover on

^^^ this here. Make sure that the car is totally dry before you cover it up, like let it sit out in the sun for a bit, raise the hood and dry out any of the grille areas and under the front edges of the bumper area. Water could have been present and you not see it because it was hidden somewhere, and when you covered it up, gave it a chance to show up. Been there and done that with mine.

[futureZ]

Originally Posted by 1JEWLDSSRS

^^^ this here. Make sure that the car is totally dry before you cover it up, like let it sit out in the sun for a bit, raise the hood and dry out any of the grille areas and under the front edges of the bumper area. Water could have been present and you not see it because it was hidden somewhere, and when you covered it up, gave it a chance to show up. Been there and done that with mine.

I did a rinseless wash on the car and thought I got all the water off. I did not check under the hood.

Thanks everyone for the thoughts and help.

[1JEWLDSSRS]

Originally Posted by futureZ

I did a rinseless wash on the car and thought I got all the water off. I did not check under the hood.

Thanks everyone for the thoughts and help.

You are welcome sir.. Yea if you don't get it totally dry under everything that the water can run to, it has a tendacy to create more moisture when you cover it up.

[acutron42]

Check any of your waxes or polishes to make sure they don't contain any animal fats. In hot humid conditions they grow mold easily. Same with interior products.