There is an internal noise that is coming from my sons 2003 GT Mustang 4.6 engine that may be coming from somewhere with in his timing chain assembly. I removed the outer drive belt to see if the sound was coming from any of outer pulleys. I then started the engine and the sound was still there. I placed my stethoscope at various areas over the timing chain cover and the sound appeared to be coming from behind the area identified by the red circle in the diagram below. Would that be the tensioner? The sound is like a metalic scraping sound. Any thoughts will be appreciated. Thank you, Tommy.