I'll just throw my 2-cents in and say that with any internal combustion engine there is always condensation that forms when first starting them but it does burn out in a short while and...some people don't run them long enough to clear the buildup and so it accumulates. This is why automotive mufflers have a small drain hole in the rear lower side. From the looks of your exhaust, and considering it's EFI with the catalytic converter, it shouldn't have any black so..it's either running rich because it isn't being run long enough to close the loop..nor burn off the water build-up, spitting some out, or/and it's using some oil for some reason oil. Clean that black off then take it out for a few solid hours and see what builds up then. Should be nothing to light gray or maybe tan.