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I started my car the other day, after moving it a few feet the previous night and all I heard was knocking LOUD slow knocking, it sounded like my car was about to blow. I shut it off to check the engine bay and did not see anything unusual. I then restarted the car and turn the a/c off and it still had the knocking sound but then it slowly went away after a/b 30 secs. I had to take a final so I drove to my school (LSU) which is a/b 15 mins away from my house. I didn't notice a significant drop in performance at all (although i did notice a slight decrease in oomph lately). I should also mention that about a week ago my battery light came on, I then drove it for 5 min parked it and came back 2 hrs. later and the light did not come on since. So has anyone had this problem or anything similar? Thanks in advance for any suggestions/help.