What happened on the main [[Mitsubishi]] article, it seems, is that an anon user vandalised the page by replacing your list of Mitsubishi-related companies with the oh-so-intelligent text "there are no problems..they are ace". Someone came along after that, noticed the vandalism but edited the article to remove the comment, instead of checking to see if the vandal had removed anything or reverting. Subsequent editors haven't realised that anything was missing.
Unfortunate, but these were not regular Wikipedia contributors deliberately ruining your work, this was an anon vandal and a newbie trying to clean up and not doing it right.
-Matt