I have not one clue as to whats causing this loud clicking or almost knocking sound in my 02 GT. I've searched and noticed other people describe something similar but I'm not sure if it's the same. It's a really loud clicking that started after a weekend of high rpms around town. When I first heard the sound I became very paranoid because ford replaced the motor less than a year ago because of a spun bearing caused a similar noise but then something odd happend. I had the superchips performance program in but I returned it back to stock since I was planning to take my car back to the dealer but after driving about 6 miles with the stock program, the noise went away. I then put the performance program back in and eventually the noise came back within an hour or so. I originally added the superchips program about two weeks ago and everything seemed to be just fine but now I'm getting the similar driverside rear engine compartment very loud clicking that others have described here. Any Suggestions or insight is highly appreciated.