hi, recently i noticed after i've been driving for about 15 minutes, steam or some kind of vapor starts wafting out from next to what i believe is the radiator. the engine temperature registers normal though. also, it might just be my imagination, but the engine noise seems to be a little more subdued ever since. any ideas as to what the problem is?

 

might have a small leak in your radiator. mine did that when it had a small hair line fracture.....