>>Unless ur raising ur own, or buying aged prime beef, most outlets add Sodium Bisulfite to redden the meat, not CO. The bisulfite will cause the diesel odor as it breaks down.
Maybe it's both then. there was a big thing on the news here about carbon monoxide being used to keep meats looking fresh.. some of the beef you buy is even 2 years old they were saying.. and none of the meat distributors supplying local grocers came forward to argue about it.