ok,so i have a 99` crown vic p71 w/ 125,000 miles on it and ever since i bought the car there has been a type of"clatter" noise coming from the front end of the motor,recently its been getting louder, and no its not knocking,i did the whole stethiscope with a pipe thing,it purrs like a kitten and its not any of the components(water pump,a/c,alternator),i tried taking the belt off and running it for a few seconds,still does it,i have a hunch its the chain,but im not quite 100 percent sure,if so,what parts exactly do i need?any help would be greatly appreciated,thank you

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