I bought my brand new trailer in July 2002 and it was bad... The mattress the most once I took the plastic wrap off of it...
I left all the windows and vents wide open during the day and even pulled the mattress out and let it sit in the sun, then left the windows cracked open at night for a couple of WEEKS.. I wasn't able to go out on it's first trip for about a month after I got it home due to work, but I'm glad I had that time to air it out first! I think it was the cabinets and the mattress that had it in my case.
Good luck!
Mitch