I bought a very lightly used OEM cover (5 uses) for my RL because I park in my driveway under a California Black Oak, which gives out a fine mist sap/resin as well as drops. They clean up with my weekend washes, but are annoying - so I decided to try the cover.
Monday I washed and dried, then went driving. Several hours later I come home and put the cover on -- the car seemed perfectly dry to me, but there was no cool down after my ride (if that matters).
The next morning it seems like moisture got underneath the cover onto the paint because when I pulled the cover off it seemed to smear some dampness - giving me streaks on the roof.
It didn't rain, I don't think sprinklers got it.

Has anyone else experienced this? Any ideas?

Thanks

 

Yep, sounds like the heat from the engine had steam or moisture get trapped under the cover, that condensed as the engine cooled down. I would say try to cool down before putting the cover on

 

Thanks 97' ! Has anyone else had similar experiences?