Hello! I'm back with the same topic "Stilo heating and fogging issues".
As I said before, the heater was powerful enough (I'd say semi-ok when compared to Marea or Bravo/-a mk1) for winter driving that I didn't get any frostbites or feel uncomfortably inside the cabin on longer journeys. But there was still a problem with fogging windows (this seems to be some kind of typical issue with Stilo M.W. if you search it via google) and this was a problem in the summer also (use of AC helps, but it won't completely remove the fog from rear windows). I was planning to do air ducts from the centre console to the rear windows, but then I noticed that the air passages/vents from the cabin to the air exit vents behind the rear bumper were fake!
I mean these:
So I took the interior of the trunk apart and found that those fake vents were actually removable pieces of plastic. It was attached with plastic "nails" or clips, which were melted to prevent opening them. Ok, brute force with a small flat driver solved that problem and I got those grills removed.
Vents were just like they should be open, but they were not. I decided to open them with a gas-powered soldering iron that had the scalpel attached to it. But, then I ran out of gas and didn't have any in reserve. I tried different knives and even a chisel with a hammer, but with no success... So, I went with the angle grinder.
After opening that vent from both sides, I put the interior of the trunk back together and this is the result:
I also found some foam blocking the exit air vents from both sides of the trunk:
That piece of foam was straightly in front of that vent, blocking it completely on both sides...
There haven't been any "real tests" yet (rainy day and four people on board) but it feels like the cabin would heat a little bit easier and faster. Waiting those sub-zero temperatures and snow, it will tell if there is any difference.
I was thinking that this "discovery" might help someone with foggy Stilo M.W., although I'm not sure if this is a common issue or just a random production quality-related thing.