Hello, im relatively new hear, and i have a 2008 Grand Prix 3.8l V8 non-supercharged. Anyways the other day i was parked beside my buddies truck talking to him and i noticed a whine. i didnt think it was my coming from my car but i revved it and it got louder almost sounded like a supercharger whine. so i open the hood and take a look and have my friend rev my car... i couldnt figure out what the matter was. so i drove a while but it still was there. then i shut the car off and turned it back on. It was gone, no more whining, Anybody know what could have caused this? Thanks!