the lord works in mysterious ways!
or maybe the lord burnt out your CEL light bulb.
prolly could be a dirty sensor somewhere. correct me if im wrong but the computer will still save old codes that came and gone, if you still want to persue what happened, get it checked and make sure it wasn't something stupid like 'engine running too lean' or something.(well that's not really stupid) but just for security. haha.
But sounds like your case solved out nicely I wish my CELs would turn off problem free!!!
good luck man
-Dewd