My 2008 Prius has been making a loud noise when engine cuts on/battery is charging. I can’t really pinpoint where it’s coming from I just know it’s louder than it used to be. No driving issues and no check engine lights. It’s just loud. 230k miles, regular maintenance and oil changes. Any ideas?
Better change the oil and look real close for metal, same with the transaxle, it could be MG1 or MG2 stator broke lose and is rubbing the case! In that case you will probably find bits of wire and insulation in the oil...but then again you would've had some serious DTC's by then as well.