03 Cobra has 30000 miles, got it tuned a few years ago, and it just randomly started knocking today. Haven't done anything different, drives fine, knocking sounds stronger from the driver side by the head, supercharger. The thing is, it has a Ford warranty until 2013. So can I take it to Ford with 2.8 and put the tune back to stock, or do I need to get a stock pulley on it? Any suggestions on what this might be or about going to dealership are appreciated, thanks.