Is it a GXP? If you have a GXP, do you have a CAI? If you answered yes to either question, it's pretty normal. Especially if you have an air leak somewhere in the system. Have you replaced the air filter? If not, it might be letting very little air through and it's time to replace it. Now if it's more of a whine then a whistle, then that's different. Where is it coming from? Do you have an auto or manual? If it's a "whine" then it could be your transmission. Just need more info because whine/whistle's are hard to diag!